The thin, six-sided granite pillars that make up Devils Postpile National Monument were created by lava erosion caused by glacier action. 1,000,000 years ago.
Fort Ord National Monument
From 1917 until its decommissioning in 1994, this 15,000-acre Federal Park was home to one of the biggest US military bases.
San Gabriel Mountains National Monument
It spans over 346,000 acres of Angels National Forest and is a hilltop in Southern California that President Obama declared to a national monument in 2014.
Mojave Trails National Monument
It is dotted with untamed mountain ranges, 550 million year old trilobite fossil beds, majestic sand dunes, and ancient lava flows.
Cabrillo National Monument
At its southernmost point, this historic region is less than a square mile in size. The naval museum on the Point Loma Peninsula is intriguing.
Berryessa Snow Mountain National Monument
This 100-mile-long paradise, which stretches from Puta Creek south of Lake Berryissa to Snow Mountain north of Cache Creek, is a little-known area in California.
Sand to Snow National Monument
One of Southern California's most significant wildlife corridors is this 154,000-acre area.
Lava Beds National Monument
Around 700 bizarre-looking lava tube caverns are scattered throughout the sculpted environment, which is also home to historical battlegrounds, campsites, and Native American rock art locations.
Muir Woods National Monument
It bears the name of Scottish naturalist, writer, and conservationist John Muir, who coined the phrase "tree-loving monument" in the nineteenth century.
Santa Rosa & San Jacinto Mountains National Monument
Located in California, the Santa Rosa and San Jacinto National Monument is a stunning mountain range covered with green pinyon, redwood, and pinyon trees.