Joshua Tree National Park is located in southeastern California. Declared a U.S. National Park in 1994 when the U.S. Congress passed the California Desert Protection Act. The park encompasses nearly 800,000 acres of the Mojave and Colorado Deserts, conserving two separate desert ecosystems at different altitudes. The name of the park is derived from the distinctive Joshua Tree, a tall-growing variety of the yucca genus that grows prevalently within its boundaries. In the higher Mojave portion of the national park, a forest of the strange Joshua Trees and a number of unique rock formations called Inselbergs are protected. In the lower Colorado portion, the Pinto Basin exhibits the typical plants of this hotter Sonoran Desert.