CASTLE MOUNTAINS NATIONAL MONUMENT
Photo: David Lamfrom, NPCA.org.
Surrounded on three sides by Mojave National Preserve in Southern California, the almost 21,000-acre Castle Mountains National Monume
JOSHUA TREE NATIONAL PARK
Originally declared a National Monument on August 10, 1936, Joshua Tree became a National Park on October 31, 1994. The park shows off rugged rock formations and stark desert
