Interlake

Interlake State Recreation Area, officially Interlake Off-Road State Recreation Area, is a 3,550-acre multi-use recreational property straddling Pike and Warrick counties in southwestern Indiana, near the town of Lynnville. The area is Indiana's largest off-road vehicle property, built on former coal mine lands that have been reclaimed and repurposed for recreation. The landscape of steep spoil banks, rolling grasslands, man-made lakes, and strip mine pits creates a diverse and unusual topography unlike any other recreational property in the Indiana state park system. With nearly 100 miles of trails and 17 lakes, Interlake offers opportunities for off-road vehicle riding, horseback riding, hiking, mountain biking, fishing, and wildlife observation across a landscape that tells the story of industrial transformation and ecological recovery.

The varied habitats created by coal mine reclamation at Interlake support a surprisingly diverse wildlife community. The 17 man-made lakes and associated wetlands attract migratory waterfowl, great blue herons, and other wading birds throughout the year. Beavers have colonized several of the waterways, creating additional wetland habitat. The reclaimed headwaters of the South Fork Patoka River provide habitat for various fish species in the lakes, which have been stocked with bass, bluegill, and catfish. White-tailed deer, coyotes, red and gray foxes, and raccoons inhabit the woodland and grassland areas. The mosaic of open grasslands, successional scrub, young forest, and mature woodland edges creates excellent habitat diversity for songbirds, raptors, and small mammals. Bird watchers find the area particularly rewarding, as the changing seasons bring different migratory species through the diverse landscape.

Interlake State Recreation Area showcases various stages of ecological succession on reclaimed coal mine lands. The three distinct periods of mining and reclamation across the property have produced a mosaic of vegetation communities at different stages of recovery. Some areas support mature deciduous woodland with oaks, hickories, and maples, while more recently reclaimed sections feature transitional communities of pioneer grasses, shrubs, and young trees. Planted pine groves provide evergreen cover in some sections, while native warm-season grasses and wildflowers colonize the open grasslands between former spoil ridges. Wetland vegetation including cattails, sedges, and emergent aquatic plants has established around the lakes and in low-lying areas. The varied topography created by mining operations produces diverse growing conditions, from dry exposed ridgetops to moist bottomlands, supporting a wider range of plant communities than would typically occur on undisturbed terrain.

Interlake State Recreation Area sits within the Illinois Basin coal region of southwestern Indiana, where Pennsylvanian-age sedimentary rocks containing multiple coal seams underlie the landscape. The surface geology has been dramatically reshaped by decades of strip mining operations that removed overburden rock and soil to access shallow coal deposits. This process created the property's characteristic landscape of linear spoil ridges, deep pits that filled with water to form lakes, and irregular terrain quite different from the original gently rolling glaciated plain. The three separate periods of mining and reclamation visible across the property represent different eras of mining technology and reclamation standards. The resulting topography, with its steep spoil banks, flat reclaimed areas, and water-filled depressions, creates an unusual geological landscape that attracts off-road vehicle enthusiasts while supporting diverse recreational opportunities.

Interlake State Recreation Area experiences a humid subtropical climate typical of southwestern Indiana, characterized by warm to hot summers and moderately cold winters. Summer temperatures regularly reach the upper 80s to low 90s Fahrenheit with significant humidity, particularly affecting riders on exposed trails. Winters bring temperatures averaging in the low 20s for lows and low 40s for highs, with approximately 15 inches of annual snowfall. Annual precipitation averages about 44 inches, with the heaviest rainfall during spring and early summer thunderstorm season. Trail conditions are significantly affected by precipitation, and trails may be temporarily closed during or after heavy rains to prevent erosion damage, particularly on the steeper spoil bank sections. Spring and fall offer the most comfortable conditions for trail riding, with moderate temperatures and generally drier conditions than the summer months.

The land now comprising Interlake State Recreation Area has a history shaped primarily by the coal mining industry that dominated southwestern Indiana's economy for over a century. Coal was mined extensively across Pike and Warrick counties beginning in the mid-nineteenth century, fueling industrial growth throughout the Midwest. The specific parcels that became Interlake underwent surface mining during several periods, with different sections mined and reclaimed at different times, creating the layered landscape of varying reclamation ages visible today. When mining operations ceased, the companies undertook reclamation as required by increasingly stringent regulations, reshaping spoil banks, establishing vegetation, and managing water quality in the pit lakes. The transition from active mining to recreation reflects a broader regional pattern across southwestern Indiana where former coal lands have been repurposed for conservation and outdoor recreation.

Interlake State Recreation Area was established as a multi-use recreational facility on reclaimed coal mine lands in southwestern Indiana. The property was developed specifically to address the growing demand for off-road vehicle recreation in the state, providing a designated area where ORV enthusiasts could ride legally on varied terrain. In 2021, management of Interlake was transferred to Indiana State Parks, along with the Redbird Off-Road State Recreation Area and the Deam Lake and Starve Hollow State Recreation Areas. This administrative change brought Interlake under the same management framework as Indiana's established state parks and recreation areas. The property has been progressively developed with improved trail systems, campground facilities, and infrastructure to support its growing visitation. Interlake has earned a reputation as a premier ORV destination, attracting riders from across the Midwest with its diverse terrain and extensive trail network.

Interlake State Recreation Area features nearly 100 miles of trails accommodating off-road vehicles, horseback riders, hikers, and mountain bikers. The trail system takes advantage of the varied terrain created by historical mining, including steep spoil bank climbs, rolling grassland sections, wooded single-track, and routes along the shores of man-made lakes. The Overlook Trail is a 1.29-mile hiking path meandering through transition woods and along a scenic lake with several picnic stops. The Observation Trail spans 1.07 miles and includes an ADA-accessible overlook for wildlife viewing in the reclaimed headwaters of the South Fork Patoka River, extending into former coal spoils for a woodland hike. The 17 lakes provide fishing opportunities for bass, bluegill, and catfish from shoreline access points. The combination of challenging ORV terrain, scenic hiking, and lake fishing makes Interlake a uniquely versatile recreational destination.

Interlake State Recreation Area is located near Lynnville in southwestern Indiana, straddling Pike and Warrick counties. Trails are open sunrise to sunset, seven days a week, though closures may occur due to hazardous weather conditions. An Indiana State Parks Annual Entrance Pass provides vehicle access to the property, but a separate Annual Off-Road Vehicle Trail-Use Permit or Daily Trail Pass is required for motorized trail access. Camping facilities include both primitive and improved sites for overnight visitors. Parking areas are available at major trailheads and lake access points. Current trail conditions can be checked by calling the park office at 812-922-0002. The nearest communities offering full services include Lynnville and Boonville. Evansville, the largest city in southwestern Indiana, is within a 30-minute drive and provides lodging, dining, and transportation services including a regional airport.

Interlake State Recreation Area represents an innovative approach to repurposing former industrial lands for recreation while continuing ecological restoration. The ongoing reclamation of coal mine lands includes managing soil chemistry, controlling erosion on steep spoil banks, and monitoring water quality in the property's 17 lakes. The Indiana Department of Natural Resources balances recreational access with ecological recovery, closing trails when wet conditions could cause excessive erosion damage. Vegetation management promotes the establishment of native plant communities on reclaimed surfaces, improving soil stability and wildlife habitat over time. The property's wetlands in the South Fork Patoka headwaters area are managed to maximize their ecological value for waterfowl, amphibians, and water quality filtration. Interlake demonstrates that former mining lands can serve dual purposes as active recreation sites and ongoing ecological restoration projects, contributing to the broader recovery of southwestern Indiana's post-mining landscape.