A desert ghost town—occupied for only 12 years—was once home to more than 500 silver mines.

California's own medieval Italian castle, authentic down to the 300-year-old iron maiden in the dungeon.

One of the ghostly stops along Route 66.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

This naturally heated mountainous creek has created a group of neon blue pools of potentially deadly boiling water.

The final resting place of a space program monolith.

An extraordinarily ornate museum in San Diego holds wondrous anthropological treasures.

This rare example of a "tidefall" is a spectacular drop from the cliffs down onto the beach.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

Experience a quartz crystal sound bath inside a storied, all-wood sound-chamber.

Once thought to be the oldest living tree in the world, Methuselah was germinated before the Egyptian pyramids were built.

A 300-ship graveyard, with a few still visible at low tide.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

An inconspicuous footbridge beloved by San Diego locals.

Eons old volcanic activity created one of the most stunning rock formations in the United States.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

Historic funicular railway, believed to be the shortest railroad in the world.

Trails through lava-carved tube-caves display sparkling bacteria and a rich history.

Canyon walls shrouded in ferns.

Carved by a waterfall in a hard-to-reach rock formation, this heart-shaped rock has inspired romantics for decades.

A meditative space out of a fantasy story.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

San Francisco's newly reopened hands-on science museum.

World-famous, Pink's still manages to keep its prized cult fetish status.