Réunion

Réunion National Park is located on the island of Réunion, a French overseas department in the western Indian Ocean approximately 420 kilometers east of Madagascar and 200 kilometers west of Mauritius ^[1]. Established on March 5, 2007, the park protects the endemic ecosystems of Les Hauts, the island's mountainous interior, covering 105,447 hectares or approximately 42 percent of the island's surface ^[2]. The landscape is dominated by two volcanoes: the dormant Piton des Neiges at 3,071 meters, the highest peak in the Indian Ocean, and the extremely active Piton de la Fournaise at 2,631 meters ^[3].

The park encompasses three spectacular cliff-rimmed cirques known as Mafate, Cilaos, and Salazie, carved by tectonic collapse and torrential erosion, along with deep ravines, dramatic waterfalls, and volcanic calderas ^[4]. Réunion is a global biodiversity hotspot, harboring more than 230 endemic plant species, 18 bird species half of which are endemic, and over 110 distinct habitat types from subtropical rainforests to ericoid heathlands ^[2].

In 2010, the park was inscribed on the UNESCO World Heritage List as "Pitons, cirques and remparts of Reunion Island," making it the first French overseas national park to receive this recognition ^[5]. With over 1,000 kilometers of marked trails, the park draws hikers and nature enthusiasts from around the world to explore its volcanic calderas, pristine forests, and remote mountain villages.

Réunion National Park protects a distinctive island fauna shaped by millions of years of isolation in the Indian Ocean. The island's rugged volcanic terrain, with elevation gradients spanning from sea level to over 3,000 meters, has produced a remarkable variety of habitats that support numerous endemic species found nowhere else on Earth. However, Réunion's fauna is also characterized by significant losses since human colonization began in the seventeenth century, with at least 22 bird species driven to extinction by habitat destruction, hunting, and the introduction of predatory mammals ^[1]. The national park now serves as the primary refuge for the island's surviving native wildlife, offering protection across the mountainous interior where most endemic species persist.

The birdlife of Réunion represents the most significant component of the island's terrestrial vertebrate fauna, with 18 resident species, half of which are endemic ^[2]. Among the most critically threatened is the Réunion cuckooshrike, known locally as the tuit-tuit, which is classified as critically endangered by the IUCN with only an estimated 30 to 40 breeding pairs surviving in a restricted 12-square-kilometer range of montane forest ^[3]. The Réunion harrier, the island's only resident bird of prey, maintains a population estimated at 200 to 300 pairs and is classified as endangered, facing ongoing threats from habitat fragmentation and collisions with power lines ^[4]. Barau's petrel, an endangered seabird endemic to Réunion, nests at high altitude on the steep cliffs around Piton des Neiges and is threatened by light pollution that disorients fledglings during their first flights to the sea, prompting an annual rescue program that saves approximately 500 birds each year ^[3].

The Mascarene petrel, one of the world's rarest seabirds and considered critically endangered, was rediscovered nesting near Piton des Neiges in 2018 after decades of uncertainty about its breeding sites ^[1]. Other notable endemic birds include the Réunion bulbul, the Réunion grey white-eye, and the Réunion stonechat, all of which inhabit the native forests within the park's boundaries. The island's rough topography, with its deep cirques and isolated valleys, has facilitated allopatric speciation, enabling populations to diverge in geographic isolation and produce distinct endemic forms over thousands of years.

Réunion has no native land mammals, with the only indigenous mammals being several species of bats that colonized the island by flight across the Indian Ocean. All other mammals present on the island today were introduced by humans, including rats, cats, dogs, goats, deer, and the tailless tenrec, which was brought from Madagascar and has become widespread across the island ^[5]. These introduced predators represent the single greatest threat to the island's native fauna, with feral cats and black rats being particularly devastating to ground-nesting birds and endemic reptiles.

The park's reptile fauna includes 13 endemic species, predominantly day geckos of the genus Phelsuma, which are among the most visible and charismatic wildlife encountered by visitors ^[6]. The Réunion day gecko and the Réunion ornate day gecko are both endemic and face competition from several introduced gecko species that have arrived from Madagascar and Mauritius. The panther chameleon, introduced to the island, has become the largest terrestrial reptile on Réunion and is commonly encountered in forested areas. The park's invertebrate fauna, while less visible, is remarkably diverse, with studies documenting a rich assemblage of endemic insects, spiders, and land snails adapted to the island's unique forest habitats.

Marine and coastal species also fall under the broader conservation umbrella of Réunion's environmental protection efforts. Hawksbill and green sea turtles nest on the island's beaches, while the tropicbird, known locally as the paille-en-queue, is an iconic coastal species frequently observed along the island's dramatic cliffs. The waters surrounding Réunion support populations of pantropical spotted dolphins and bottlenose dolphins, adding to the island's overall biodiversity significance as a critical refuge for Indian Ocean wildlife.

The flora of Réunion National Park is among the richest and most distinctive of any oceanic island in the world, reflecting the island's volcanic origins, dramatic altitudinal gradients, and millions of years of isolation in the Indian Ocean. Of the approximately 850 known native plant species on Réunion, around 230 are endemic to the island, and roughly half of those endemics are classified as endangered ^[1]. The park's 105,447 hectares encompass more than 110 distinct habitat types, organized along an altitudinal gradient from lowland forests near the coast up to sparse alpine vegetation on the summit of Piton des Neiges at 3,071 meters. The density of forest endemics on Réunion is extraordinary, averaging 41 endemic tree species per hectare, a figure three times higher than Hawaii and five times higher than the Galapagos Islands.

The lowland rainforests, found primarily between 750 and 1,100 meters on the windward eastern slopes, represent the most species-rich plant communities in the Mascarene Islands. These forests have a canopy reaching up to 30 meters in height and are characterized by abundant shrubs in the coffee family, including species of Gaertnera, Chassalia, and Bertiera, alongside the endemic bamboo known locally as calumet ^[2]. The understory harbors numerous species of orchids, including genera such as Angraecum and Bulbophyllum, and a remarkable diversity of ferns that thrive in the consistently humid conditions. The Mare Longue Biological Reserve, a 68-hectare protected area within the park, preserves the last remaining lowland rainforest in the Mascarene archipelago, sheltering 200 plant species including 30 percent of Réunion's indigenous flora and the endemic whitewood tree ^[3].

Cloud forests dominate the middle elevations, occurring between 800 and 1,900 meters on the wetter eastern slopes and between 1,100 and 2,000 meters on the drier western side, where annual rainfall ranges from 2,000 to 10,000 millimeters ^[2]. These mist-shrouded forests are draped in mosses, lichens, and epiphytic orchids, with conspicuous stands of red marron and canne marron adding splashes of color to the verdant canopy. Emergent tree ferns tower above the understory, and the endemic Réunion palm contributes to the distinctive structural character of these mid-elevation forests. Seven of the orchid species found in these forests are endemic to Réunion, making the island a site of particular interest for orchid conservation and research.

Above the cloud forest belt, between approximately 1,500 and 1,900 meters, lies an elfin forest zone dominated by the endemic upland tamarin des hauts, a species of acacia that forms dense stands interspersed with the endemic bamboo calumet and Réunion heath ^[2]. The tamarin forests of the highlands are among the most iconic landscapes within the park, covering vast slopes with a silvery-green canopy that contrasts sharply with the dark volcanic rock beneath. These forests provide critical habitat for several endemic bird species, including the endangered Réunion cuckooshrike, which relies on the native canopy for foraging and nesting.

At the highest elevations, above 1,900 meters, the vegetation transitions to ericoid heathlands and sparse alpine grasslands that cling to the volcanic summits and ridgelines. This highland vegetation, which accounts for approximately 16 percent of the park's total area, is characterized by ericoid thickets, the small endemic tree Sophora denudata, and grasslands rich in endemic grasses and orchids, including the striking terrestrial orchid Disa borbonica ^[2]. The mineral-rich volcanic soils at these altitudes support a highly specialized flora adapted to extreme conditions including strong winds, intense solar radiation, and temperatures that can approach freezing during the austral winter.

The overall distribution of vegetation within the park follows a clear altitudinal pattern: lowland forests cover approximately 8.2 percent of the protected area, mid-level forests account for 15.6 percent, and high-level forests make up 43.1 percent, with roughly half of the forest area classified as tropical rainforest ^[2]. Less than 25 percent of Réunion's original native vegetation remains, mostly restricted to the higher altitudes where the park provides its most critical protection. The Mascarene forests ecoregion, which includes Réunion along with Mauritius and Rodrigues, has been classified as endangered by the World Wildlife Fund, underscoring the global conservation importance of the native plant communities that survive within the national park's boundaries.

Réunion National Park encompasses one of the most geologically dynamic landscapes on Earth, shaped by the interplay of volcanic activity, massive gravitational collapses, and intense tropical erosion over millions of years. The island of Réunion itself is the surface expression of a volcanic hotspot that has been active for approximately five million years, with the island emerging from the Indian Ocean floor about two million years ago ^[1]. The same hotspot is believed to have created the Deccan Traps in India approximately 66 million years ago before the Indian tectonic plate migrated northward, leaving a trail of volcanic seamounts and islands culminating in the Mascarene archipelago. Réunion is the youngest and most volcanically active island produced by this hotspot, sharing geological kinship with the Hawaiian Islands, which were formed by an analogous process in the Pacific Ocean.

The island is composed of two overlapping shield volcanoes that together create an elliptical landmass measuring approximately 50 by 70 kilometers. Piton des Neiges, the older and larger of the two, occupies the northwestern two-thirds of the island and rises to 3,071 meters above sea level, making it the highest point in the Indian Ocean ^[2]. This massive shield volcano began constructing its subaerial edifice approximately 2.1 million years ago and progressed through several distinct phases of activity, including periods of intense effusive eruptions interspersed with quiescent intervals and at least one major Plinian eruption dated to approximately 188,000 years ago that coincided with the formation of a large caldera ^[3]. Piton des Neiges has been dormant for at least 20,000 years, though some geochronological studies suggest its last eruption may have occurred as recently as 27,000 years ago.

The three cirques of Mafate, Cilaos, and Salazie are among the most visually striking geological features within the park, each forming a roughly circular amphitheater approximately 10 kilometers wide with vertical walls plunging more than 1,000 meters to the valley floors below. Contrary to early assumptions, these cirques were not carved by glaciers but instead formed through a combination of tectonic collapse of the original volcanic dome and subsequent scouring by torrential erosion from the island's extreme rainfall ^[4]. The resulting landscape of towering ramparts, isolated plateaus called îlets, and narrow gorges represents one of the most dramatic examples of volcanic erosion anywhere on the planet. Large submarine debris-avalanche deposits found on the ocean floor surrounding Réunion provide additional evidence of the catastrophic flank collapses that shaped these cirques over hundreds of thousands of years.

Piton de la Fournaise, the younger and currently active volcano, occupies the southeastern third of the island and has been building its edifice for approximately 530,000 years, initially on the flanks of Piton des Neiges ^[5]. This basaltic shield volcano is one of the most active on Earth, with at least 188 documented eruptions since 1640 and an average eruption frequency of one event every nine months in recent decades ^[5]. The summit is crowned by two craters: the larger Dolomieu crater and the smaller Bory crater on its southern flank. The volcano's activity is concentrated within the Enclos Fouqué caldera, a horseshoe-shaped depression approximately 8 kilometers wide that opens toward the sea on the eastern side, formed through progressive eastward slumping over the past 250,000 years.

The eruption of February 2026 demonstrated the ongoing geological vitality of Piton de la Fournaise, with lava flows extending seven kilometers from the eruptive vent on the southeastern flank near Piton Morgabim and reaching the Indian Ocean, cutting one of the island's main coastal roads for the first time since 2007 ^[6]. Like its Hawaiian counterparts, Piton de la Fournaise produces predominantly effusive eruptions of fluid basaltic lava, creating both smooth pahoehoe and rough aa flow types that progressively extend the island's coastline. The Piton de la Fournaise Volcano Observatory, operated by the Institut de Physique du Globe de Paris, provides continuous seismic, deformation, and geochemical monitoring of the volcano, enabling authorities to manage access to the caldera and ensure visitor safety during periods of elevated activity.

The geological processes that shaped Réunion continue to transform the landscape at an extraordinary pace. The combination of intense volcanic activity building new terrain and extreme precipitation eroding it away creates a dynamic equilibrium that has produced the island's distinctive scenery of towering peaks, vertical-walled canyons, and cascading waterfalls. The UNESCO World Heritage inscription specifically recognized these geological features, noting that the "combination of volcanism, tectonic landslide events, heavy rainfall, and stream erosion" has produced a rugged landscape of exceptional natural beauty that provides outstanding examples of ongoing geological processes ^[4].

Réunion National Park experiences a tropical oceanic climate that is dramatically modified by the island's extreme topography, creating one of the most varied microclimatic mosaics of any protected area in the world. Positioned just south of the Tropic of Capricorn at approximately 21 degrees south latitude, the island lies in the path of the southeast trade winds, which bring moisture-laden air from the Indian Ocean and drive it against the volcanic slopes, producing extraordinary orographic rainfall on the windward eastern side and a pronounced rain shadow on the leeward west ^[1]. The altitudinal range within the park, spanning from approximately 200 meters to the 3,071-meter summit of Piton des Neiges, further amplifies climatic variation, with conditions transitioning from tropical at the coast to near-alpine at the highest elevations.

The island's year is divided into two distinct seasons: a hot, humid austral summer from November through April and a cooler, drier austral winter from May through October. Average coastal temperatures range from approximately 17 degrees Celsius to 27 degrees Celsius throughout the year, with the warmest months seeing daily highs around 30 degrees Celsius at sea level ^[2]. Within the park's mountainous interior, temperatures are considerably cooler, dropping below 10 degrees Celsius during winter nights in the cirques and approaching freezing at the summit of Piton des Neiges, where occasional frost and even rare snowfall have been recorded. This temperature gradient supports the distinct vegetation zones that characterize the park, from tropical rainforest at lower elevations through cloud forest and tamarin woodland to ericoid heath at the summits.

Réunion holds some of the most extraordinary rainfall records on the planet, a testament to the extreme orographic enhancement produced by its steep volcanic terrain. The island's official 24-hour rainfall record of 1,825 millimeters was set at Foc-Foc during Tropical Storm Denise on January 7 to 8, 1966, a figure recognized by the World Meteorological Organization as the greatest verified 24-hour precipitation total in recorded history ^[3]. During Tropical Cyclone Gamede in February 2007, the Cratère Commerson rain gauge shattered multiple world records, recording 3,929 millimeters in 72 hours and an astonishing 5,512 millimeters over nine days, amounts unprecedented in global meteorological records ^[4]. These extraordinary totals are driven by the combination of warm, moisture-rich tropical air masses and the island's dramatic topography, which forces rapid uplift and condensation.

The distribution of rainfall across the island is remarkably uneven. The eastern windward coast and interior slopes receive annual precipitation exceeding 3,000 millimeters, with some elevated sites recording more than 6,000 millimeters per year as persistent orographic uplift wrings moisture from the trade winds ^[1]. By contrast, the western leeward coast from Le Port to Saint-Pierre receives less than 1,000 millimeters annually, creating a semi-arid environment that contrasts starkly with the lush forests just kilometers away on the opposite side of the island. Within the park's cirques, rainfall patterns vary considerably depending on aspect and elevation, with the Cirque de Salazie being notably wetter than the more sheltered Cirque de Cilaos.

Réunion lies within the southwestern Indian Ocean tropical cyclone basin, with the official cyclone season running from November 1 through May 15, though the most dangerous storms typically occur between late December and mid-April ^[2]. Cyclone Hyacinthe in January 1980 and Cyclone Gamede in February 2007 rank among the most significant weather events in the island's history, both producing catastrophic flooding, landslides, and rainfall totals that rewrote world records. The park's steep terrain makes it particularly vulnerable to cyclone-driven erosion and landslides, which periodically reshape trails, bridges, and mountain paths within the cirques. The best period for visiting the park is during the austral winter from mid-May through October, when the weather is generally cooler and drier, skies are clearer for mountain views, and the risk of tropical cyclones is effectively nil.

Unlike many other lands in the Indian Ocean, Réunion was entirely uninhabited before the arrival of European sailors, meaning the island has no indigenous population or pre-colonial human history. Arab and Swahili traders were the first to document the island's existence, referring to it as Dina Morgabin, meaning "Western Island," in medieval navigational texts, though there is no evidence they established permanent settlements ^[1]. Portuguese mariners are believed to have sighted the island in the early sixteenth century, but it was the French who would ultimately claim and colonize Réunion, transforming it from an uninhabited volcanic island into a complex colonial society whose cultural legacy profoundly shapes the region to this day.

French interest in the island began in 1638 when sailors from Saint-Malo were shipwrecked on its shores and reported favorably on its potential for colonization. In 1642, the French began sending expeditions to the island, and in 1646 a group of twelve mutineers were banished there from the French settlement at Fort Dauphin on southern Madagascar ^[1]. Based on their reports of the island's fertility and favorable conditions, France officially claimed the territory in 1649, naming it Île Bourbon after the ruling French dynasty. Formal colonization commenced in 1665 when the French East India Company dispatched twenty settlers under the leadership of Étienne Regnault, who became the first governor of the fledgling colony ^[2].

The colonial economy that developed on Île Bourbon was built upon the cultivation of tropical cash crops, most importantly coffee in the eighteenth century and later sugarcane, which required a vast labor force that the small European settler population could not provide. Beginning in the late seventeenth century, enslaved people were brought to the island in large numbers from East Africa, Madagascar, India, and Southeast Asia to work the plantations ^[3]. Between 1769 and 1793, approximately 80,000 enslaved people were imported to Réunion and neighboring Mauritius combined, with roughly 45 percent supplied through the Sakalava slave trade networks of northwestern Madagascar, which raided East Africa and the Comoro Islands for captives ^[4].

The practice of marronage, in which enslaved people escaped into the island's rugged and largely uninhabited mountainous interior, became a defining feature of Réunion's cultural geography. The escaped slaves, known as maroons, took advantage of the inaccessible cirques and deep ravines to establish hidden communities far from the coastal plantations ^[5]. The three great cirques of the island bear names derived from these maroon communities: Mafate, meaning "the one that kills," Salazie, meaning "the good camp," and Cilaos, from the Malagasy word Tsilaosa, meaning "that one does not abandon" ^[6]. Archaeological excavations have uncovered a remarkable hidden settlement in the Cirque de Cilaos at an altitude exceeding 2,200 meters, a secret valley measuring 450 meters in length sheltered between vertiginous 50-meter rock faces, where maroons lived in defiance of the colonial authorities who employed professional slave hunters to track them down ^[7].

Slavery was abolished on Réunion on December 20, 1848, following a decree announced by Commissioner Joseph Napoléon Sébastien Sarda Garriga on October 18 of that year, liberating the island's approximately 60,000 enslaved inhabitants ^[2]. The resulting labor shortage on the sugar plantations was addressed through the importation of indentured laborers, primarily from southern India, with approximately 75,000 Hindu workers arriving by 1865, followed by Muslim immigrants from Gujarat at the beginning of the twentieth century ^[1]. This successive layering of peoples from Africa, Madagascar, India, China, and Europe produced Réunion's uniquely diverse Creole society, in which elements of French, African, Indian, and Malagasy culture blend in cuisine, language, music, and religious practice. The island's Creole identity remains a source of profound cultural pride and is reflected in the traditions of the mountain communities within the national park's boundaries, particularly in the remote villages of the Cirque de Mafate, which remain accessible only on foot or by helicopter.

The movement to formally protect Réunion's mountainous interior gained momentum throughout the late twentieth century as increasing development pressures, invasive species, and deforestation threatened the island's remaining native ecosystems. France had established a system of national parks beginning in 1963, but it was not until the early 2000s that serious efforts were undertaken to create a national park on Réunion, driven by growing recognition that the island harbored globally significant biodiversity concentrated in its highland forests and volcanic landscapes. After years of consultation among government agencies, local communities, and environmental organizations, Réunion National Park was officially established by decree on March 5, 2007, becoming the ninth national park in the French system and the first to be created in a French overseas department under the revised 2006 national parks law ^[1].

The park was structured with two distinct zones reflecting a balance between strict nature protection and sustainable community development. The core zone, known as the coeur du parc, encompasses the most ecologically sensitive areas of the mountainous interior, where regulations restrict construction, resource extraction, and other activities that could degrade the natural environment. Surrounding this core is the adherent zone, or aire d'adhésion, where municipalities voluntarily join the park's management framework and commit to sustainable development principles in exchange for technical support and funding. Together these zones cover 105,447 hectares, approximately 42 percent of the island's total land area ^[2]. In April 2007, the park's Administrative Council took office, and between 2007 and 2009, staff were hired and operational infrastructure established across the territory.

A pivotal moment in the park's young history came on August 1, 2010, when the UNESCO World Heritage Committee inscribed the "Pitons, cirques and remparts of Reunion Island" on the World Heritage List under criteria vii (superlative natural phenomena) and x (significant habitats for biological diversity) ^[3]. This inscription recognized the outstanding universal value of the volcanic landscapes, the dramatic cirques and ramparts, and the exceptional concentration of endemic species within the park's boundaries. The designation made Réunion the first French overseas territory to receive World Heritage recognition for a natural site, elevating the park's international profile and strengthening the case for continued investment in conservation and sustainable tourism infrastructure.

The park charter, approved by decree on January 21, 2014, established a ten-year management framework for both the core and adherent zones, defining objectives for biodiversity conservation, sustainable development, cultural heritage preservation, and environmental education ^[4]. This charter simultaneously serves as the management plan for the UNESCO World Heritage site, ensuring that international conservation standards are integrated into day-to-day park operations. Twenty of the island's 24 communes voted to adhere to the charter, demonstrating broad community support for the park's mission. The charter was inaugurated with significant political attention, and on August 21, 2014, French President François Hollande personally inaugurated the Maison du Parc visitor center at La Plaine-des-Palmistes, signaling national commitment to the park's development ^[5].

The park's governance structure reflects the complexity of managing a protected area that includes inhabited communities and overlapping jurisdictions. An Administrative Council of 88 members, composed primarily of local elected representatives alongside national government appointees and scientific advisors, oversees policy decisions and budget allocation, with members serving six-year terms ^[1]. The park employs rangers, scientists, and community liaisons who work across the territory to enforce regulations, conduct biodiversity monitoring, manage trails, and engage with local populations. Partnerships with research institutions including the University of Réunion, CIRAD, and the Conservatoire Botanique National de Mascarin provide scientific expertise that informs management decisions.

In June 2020, two new Directed Biological Reserves were formally created within the park's boundaries: the Bois de couleur des bas forest reserve and the Saint-Philippe coast reserve, together covering nearly 300 hectares and protecting two extremely rare low-altitude habitat types in the Mascarene Islands ^[6]. These additions represented an important expansion of protection for lowland ecosystems that had previously received less attention than the highland forests. The park continues to evolve as an institution, adapting its management strategies to address emerging threats from climate change, increasing visitor pressure, and the persistent challenge of invasive species while maintaining its commitment to integrating conservation with the livelihoods and cultural identity of the island's highland communities.

Réunion National Park offers one of the most extensive and dramatic hiking networks in the Indian Ocean, with over 1,000 kilometers of marked trails traversing volcanic calderas, cloud forests, sheer-walled cirques, and alpine summits. The trail system is anchored by three long-distance Grande Randonnée routes, designated GR R1, GR R2, and GR R3, which together provide multi-day itineraries through the most spectacular landscapes on the island. These routes, maintained by the Office National des Forêts and park staff, attract thousands of trekkers annually who come to experience terrain that ranges from tropical lowland forest to barren volcanic lava fields at elevations exceeding 3,000 meters.

The GR R1 is a circular route of approximately 60 kilometers that loops around Piton des Neiges, passing through all three of the island's great cirques: Mafate, Cilaos, and Salazie ^[1]. Typically completed in four to six days, this trail offers hikers an immersive experience of the park's most iconic landscapes, from the lush subtropical forests of Salazie to the isolated mountain villages of Mafate, which are accessible only on foot or by helicopter. The route traverses high mountain passes including the Col des Boeufs at approximately 1,940 meters, which serves as the gateway between Salazie and Mafate, and involves significant cumulative elevation gain as hikers descend into and climb out of each successive cirque.

The GR R2, known as the Grande Traversée, is the island's premier long-distance trail, crossing Réunion from north to south over approximately 130 to 140 kilometers with roughly 8,000 meters of cumulative elevation gain ^[2]. Beginning in Saint-Denis on the northern coast, the route passes through the Cirque de Mafate, climbs to the Col de Fourche, descends into the Cirque de Cilaos, and continues south across the volcanic landscapes of Piton de la Fournaise before terminating at the coastal town of Saint-Philippe in the southeast. The traverse typically requires 10 to 14 days and is considered one of the finest multi-day hikes in the French-speaking world, demanding good physical fitness and experience with mountain terrain. Along the route, hikers stay in a network of mountain lodges known as gîtes, which provide basic accommodation, meals, and a communal atmosphere.

The GR R3 offers a focused exploration of the Cirque de Mafate, following a circuit of approximately 39 kilometers over five days through this roadless wilderness ^[3]. Mafate is widely regarded as the most spectacular and remote of the three cirques, with scattered hamlets such as La Nouvelle, Marla, and Aurère perched on isolated plateaus surrounded by vertical ramparts rising over 1,000 meters. The trail connects these communities through a network of steep paths that descend into ravines and climb back to ridge crests, offering constantly changing perspectives of the cirque's dramatic geology.

The ascent of Piton de la Fournaise is the most popular single-day hike in the park, consistently rated as the top trail on the island with a 4.7-star rating from over 1,700 reviews ^[4]. The standard route begins at Pas de Bellecombe, situated on the rim of the Enclos Fouqué caldera, from where hikers descend into the caldera and cross a surreal lunar landscape of solidified lava flows to reach the base of the summit cone. The round-trip distance is approximately 11 kilometers with 500 meters of elevation gain, and most hikers complete it in four to six hours. Access to the caldera is strictly regulated and may be closed during periods of volcanic activity, as determined by the Piton de la Fournaise Volcano Observatory monitoring data.

The summit of Piton des Neiges, the highest point in the Indian Ocean at 3,071 meters, is typically approached as a two-day hike from the town of Cilaos, with an overnight stay at the Gîte de la Caverne Dufour at approximately 2,478 meters ^[5]. Hikers depart the gîte well before dawn to reach the summit for sunrise, which on clear mornings reveals panoramic views encompassing the entire island, the three cirques, and the distant Indian Ocean horizon. The final ascent involves scrambling over rocky terrain and can be cold and windy, requiring warm layers even in the tropical climate.

Among the park's most dramatic natural attractions is the Trou de Fer, a collapsed volcanic crater that sinks to a depth of 300 meters, collecting four separate waterfalls with a combined drop of 725 meters ^[6]. A sturdy viewing platform reached by a relatively easy 3.5-kilometer hike from the Gîte de Bélouve provides a vertiginous perspective into this chasm. The hike passes through the ancient Forêt de Bélouve, a pristine primary forest at 1,500 meters altitude that is protected as a biological reserve and harbors native tree ferns, tamarin des hauts, and numerous endemic orchid species. Other notable trail destinations include the Cascade du Voile de la Mariée in Salazie, the viewpoint at Le Maïdo overlooking the full extent of the Cirque de Mafate, and the volcanic Plaine des Sables, a vast desert of volcanic ash and cinder that resembles a Martian landscape.

Réunion National Park operates without entrance fees, allowing free access to all visitors throughout the core zone and adherent zone of the protected area ^[1]. This open-access policy reflects the park's philosophy of integrating conservation with community life on an island where approximately 42 percent of the territory falls within park boundaries. Unlike many national parks that function as discrete, fenced-off reserves, Réunion's park encompasses inhabited communities, working agricultural land, and public roads, making it an integral part of daily life for the island's residents and an easily accessible destination for visitors.

The Maison du Parc, the park's primary visitor center, is located in the town of La Plaine-des-Palmistes on the eastern side of the island and was inaugurated on August 21, 2014, by French President François Hollande ^[2]. The facility houses a permanent exhibition titled "Réunion, island of nature, heart of people," which explores the island's geological origins, endemic biodiversity, and the cultural traditions of its highland communities. Interactive displays, topographic models, and short documentary films help visitors understand the formation of the cirques, the volcanic processes of Piton de la Fournaise, and the conservation challenges facing the park's ecosystems. The surrounding grounds feature gardens planted with native species, providing an introduction to the distinctive flora visitors will encounter on the trails.

Accommodation within the park is primarily provided through a network of mountain gîtes, or lodges, which are essential infrastructure for multi-day hiking routes (as of March 2026). These gîtes range from basic dormitory-style shelters to more comfortable facilities offering private rooms and prepared meals. The Gîte de la Caverne Dufour, situated at approximately 2,478 meters on the slopes of Piton des Neiges, serves hikers attempting the summit and provides bunk beds, blankets, and evening meals in a high-altitude setting ^[3]. The Gîte de Bélouve, located at the edge of the ancient primary forest, offers both indoor accommodation and a camping area with sanitary facilities, serving as a base for hikes to the Trou de Fer viewpoint and through the Forêt de Bélouve ^[2]. Within the Cirque de Mafate, several gîtes in the villages of La Nouvelle, Marla, Aurère, and Ilet à Malheur provide the only accommodation options in this roadless wilderness, and advance booking is strongly recommended during the peak hiking season from May through October.

Getting to and around Réunion National Park requires some planning, as the island is served by a single international airport, Roland Garros Airport near the capital Saint-Denis, with flights connecting primarily to Paris, Madagascar, Mauritius, and other Indian Ocean destinations. Within the island, a rental car is the most practical means of reaching trailheads and park access points, as public transportation to the highland areas is limited (as of March 2026) ^[1]. The main roads ascending to the park are narrow and extremely winding, climbing from near sea level to elevations of 2,000 to 2,500 meters over short distances, and require careful driving. The Route Nationale 3, connecting Saint-Pierre in the south to the park interior, and the road from Saint-André to the Cirque de Salazie are the primary vehicular approaches. The Route Forestière du Volcan, leading to Pas de Bellecombe and the Piton de la Fournaise trailhead, is one of the most scenic drives on the island.

The towns at the entrances to the cirques serve as staging areas for hikers and offer a range of services including restaurants, small hotels, shops, and outdoor equipment rental. Cilaos, nestled within its namesake cirque, is the largest of these gateway communities and features thermal baths, a tourism office, and numerous accommodation options ranging from guesthouses to small hotels. Hell-Bourg, located in the Cirque de Salazie and classified as one of the "Most Beautiful Villages of France," provides a charming base with Creole architecture, restaurants serving traditional cuisine, and easy access to trails leading into the park. The Cirque de Mafate, being entirely roadless, can only be reached on foot from trailheads at Col des Boeufs or by helicopter from several locations around the island, making it the most logistically challenging but also the most rewarding destination for experienced hikers.

Hikers planning multi-day treks within the park should be aware that weather conditions can change rapidly in the mountains, with fog, heavy rain, and cold temperatures possible at higher elevations even during the dry season (as of March 2026). Trail conditions vary seasonally, with some paths becoming difficult or dangerous during and after heavy rains due to mudslides and swollen river crossings. The park provides trail condition updates and safety advisories, and hikers are advised to register their itineraries at local tourism offices or gîtes before setting out on longer routes. Mobile phone coverage is limited or absent in many areas within the park, particularly in the Cirque de Mafate and on the volcanic plateau, making self-sufficiency and proper preparation essential.

The conservation challenges facing Réunion National Park are among the most complex of any protected area in the world, driven by the collision between extraordinary endemic biodiversity and the devastating impacts of invasive alien species on an isolated oceanic island. A 2017 IUCN assessment downgraded the Réunion World Heritage site from "good with some concerns" to "significant concern," primarily due to the escalating threat posed by invasive species and the difficulty of controlling their spread across the park's rugged terrain ^[1]. This downgrade underscored the urgency of conservation action and focused international attention on the need for sustained, well-resourced management interventions to protect the island's irreplaceable natural heritage.

Invasive alien species represent the single greatest ecological threat to the park, with 129 invasive alien species documented across the island, including at least 27 invasive alien plants that have proven extremely difficult to eradicate ^[2]. Giant bramble, guava, Mauritius hemp, lantana, privet, common gorse, and black wattle are among the most aggressive plant invaders, capable of transforming native forest into dense monocultures that exclude endemic species. These invasive plants have already colonized significant portions of the island's native habitat, particularly at lower elevations where human disturbance has created openings for establishment. A comprehensive study led by CIRAD and local partners identified 60,303 hectares as priority conservation areas, of which 4,392 hectares require active restoration of vegetation already invaded by alien plants and 16,019 hectares need ongoing monitoring to prevent future invasion ^[2].

Invasive animals compound the threat to native ecosystems, with eight alien mammal species including deer, goats, rats, cats, and dogs causing widespread damage alongside six introduced bird species, four fish species, one reptile, and 18 invertebrates ^[1]. Black rats and feral cats are particularly devastating to the island's endemic bird populations, predating eggs, chicks, and adult birds in native forests. The Réunion cuckooshrike, with only an estimated 30 to 40 breeding pairs remaining, faces an existential threat from rat predation of nests in its tiny 12-square-kilometer range ^[3]. Introduced deer and goats browse on native vegetation, preventing forest regeneration and opening pathways for invasive plant establishment, while feral dogs occasionally attack ground-nesting birds.

The park and its partners have developed a multi-pronged conservation strategy that combines direct intervention, scientific research, and community engagement. A working group coordinated by CIRAD brings together the Réunion National Park, the University of Réunion, the Office National des Forêts, and the Conservatoire Botanique National de Mascarin to develop evidence-based management plans for invasive species control ^[2]. This action-research project, operational since 2018, employs comprehensive data analysis to identify priority zones for intervention based on operational criteria including invasion fronts, accessibility, and alignment with existing management operations. Annual reassessment of the intervention program ensures that resources are directed where they can achieve the greatest conservation impact.

Species-specific conservation programs target the most critically endangered endemic wildlife within the park. The annual Barau's petrel rescue program collects approximately 500 disoriented fledglings each year that have been grounded by artificial light pollution during their first flights to the sea, rehabilitating and releasing them to bolster the breeding population ^[3]. Rat control programs using bait stations have been deployed around known Réunion cuckooshrike nesting sites to reduce predation pressure on this critically endangered species. The rediscovery of the Mascarene petrel nesting near Piton des Neiges in 2018 prompted new research efforts to understand the breeding ecology of this extremely rare seabird and develop targeted protection measures ^[1]. The creation of two new Directed Biological Reserves in 2020, protecting the Bois de couleur des bas forest and the Saint-Philippe coast, extended formal protection to critically threatened lowland habitats that harbor some of the island's most endangered plant species ^[4].

Long-term ecological monitoring provides the scientific foundation for the park's conservation work. The Mare Longue Biological Reserve maintains three permanent forest plots that have been continuously monitored since 1990, with every tree inventoried, tagged, and measured to track changes in forest composition and health over time ^[4]. The park participates in international knowledge-sharing initiatives, including a partnership with Table Mountain National Park in South Africa through the FEXTE project, which focuses on exchanging expertise in invasive species management and ecosystem restoration ^[5]. New species continue to be discovered within the park's boundaries, such as the flowering plant Heterochaenia fragrans, first described by botanists in 2008, reminding scientists that the park's biodiversity has not yet been fully catalogued and that protection of intact habitats remains essential for preserving species that may not yet be known to science ^[1].