The lowest point in South Dakota and the source of the Minnesota River.

An entire city block built completely out of petrified wood.

Every president in history is immortalized in bronze in downtown Rapid City.

Thanks to a loophole in property ownership, this alleyway has become a cacophonous street gallery.

The ravine where Jesse James supposedly performed an impossible jump to evade capture.

Hidden behind Lincoln's head is a 70-foot-long chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

In the middle of the desert, miles from any human life, sat an anomalous pay phone that still magically answers your calls.

A volcanic tunnel illuminated by natural skylights offers a shaded respite from the desert sun.

A massive hydrovolcanic explosion left a half-mile wide crater in Death Valley.

The highest dunes in California are the most likely place in the area to hear the Singing Sands.

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

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

James Turrell's total color immersion art installation, hidden on the top floor of a luxury handbag shop.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

Art from the latest counter-culture; kids who dye their hair blue and believe the future will be a post-apocalyptic water world.

This private residence was the template for one of the most beloved television homes of all time.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

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

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

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

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

A psychedelic labyrinth on the San Francisco bay.

An artsy hidden staircase leads to breathtaking views of San Francisco.