Elephant Butte Lake State Park surrounds New Mexico’s largest reservoir, a 36,000-acre lake on the Rio Grande created by Elephant Butte Dam and stretching about 40 miles with more than 200 miles of shoreline. The dam grew out of water disputes that began in the 1880s among farmers in southern New Mexico, Texas, and Mexico, and after years of legal delays it was built from 1911 to 1916 to control flooding, regulate irrigation, and generate electricity. Today the park is the state’s largest and a major recreation area, while the site also preserves the history of a socially segregated dam-building community and a 2014 stegomastodon fossil discovery.