One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

See six states, pickled freaks, rocks, and antiques.

The largest self-built castle in the U.S., six decades in the making.

A little-known hot spring haven right below the highway.

A collection of fading fantasy tchotchkes lines this dirt road in the Colorado wilderness.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

Finale of "William Tell Overture" can be heard as drivers pass over grooves in the road.

Ten 25-foot-tall, beehive-shaped kilns, abandoned in Death Valley.

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

Towering basalt columns, a creation of fire and ice.

This sun-scorched lakebed contains samples of half the natural elements known to humankind.

One of the most unusual geological features, recognizable from a dozen hit movies.

A dwindling menagerie of anthropomorphic oil derrick animals still dot the barren California landscape.

The rocks in this arid basin leave trails of movement behind them.

One of the last free public hot springs is decorated with hippie art.

A water tower shaped like a giant coffee pot looms over a small Swedish village in Central California.

Quite simply the largest tree in the world (by volume).

Four hundred granite steps were built into this massive rock by the National Park Service.

These millipedes glow not out of attraction, but as a not-too-subtle warning.

This desert oddity hides in plain sight thanks to a cartographic error and a desert explorer with a punny sense of humor.

Travelers leave tea kettles in a remote part of Death Valley as part of a mysterious, decades-old tradition.