United States
32.9830°, -111.5330°
March 2, 1889
2
Casa Grande Ruins National Monument preserves the remains of a Hohokam farming community and the mysterious four-story Casa Grande structure built around 1350 CE. The monument protects one of the largest prehistoric structures ever built in North America and provides insight into the sophisticated irrigation-based civilization of the Sonoran Desert. Archaeological evidence shows the site was occupied for over 1,000 years before being abandoned around 1450 CE. The monument is managed by the National Park Service (NPS).