Casa Grande Ruins National Monument

Casa Grande Ruins National Monument in Coolidge, Arizona preserves the largest protected Hohokam site in the United States. The centerpiece is the four-story Great House, completed around 1350 AD using approximately 3,000 tons of caliche, standing 60 feet wide with walls four feet thick at the base. Internal support timbers of juniper, pine, and fir were transported from forests up to 60 miles away. The structure likely served for celestial observation and irrigation management. Designated the nation's first archaeological reserve in 1892 by President Benjamin Harrison, the monument protects over 60 pre-contact sites dating from 1150-1350 AD. For the Akimel O'odham, Hopi, and Zuni peoples, it remains a sacred ancestral place.