Volcanic slopes in Pinnacles National Park, California

© Don Smith/Getty Images

Volcanic slopes in Pinnacles National Park, California

Pinnacles was established as a national park just three years ago, in 2013. That makes it the newest national park in the United States, but its namesake features—these rock spires—were millions of years in the making. Roughly 23 million years ago, volcanos erupted to form a 30-mile-wide volcanic field, which was then split in two by a shift in the San Andreas fault. The western side of the field gradually moved nearly 200 miles north, all the while being eroded by water, ice, and wind.

The rock that’s left behind is now shaped into these pinnacles. The towering spires attract rock climbers, to be sure, but they also provide homes for many species of animals, including the California condor. In fact, this is just one of four places where captive-bred condors are released into the wild. And the pinnacles aren’t the only amazing rock formations in this park—it’s also distinguished by unusual talus caves, which were formed when massive boulders were wedged into narrow ravines. So when the searing heat of Pinnacles National Park gets to be too much for you, catch a little shade beneath these house-sized boulders.