A hidden subterranean installation offers a view of the sky.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

Visible below the waves are memorials to the city's Gold Rush dead.

A modern mechanical planetary system, part of a 10,000 year clock.

Floating man-made island and upscale restaurant.

"Only the devil could play golf here."

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

One of the ghostly stops along Route 66.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

Big gun installations, built over a massive cemetery, now abandoned & hidden in trees.

A former utopian healing center created by a huckster and built by derelicts.

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

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

An essential stop before plundering, BYO Cutlass.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

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

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

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

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.