The only theatre in the world constructed specifically for sound movement.

Odd outsider art installations surround a Gold Rush-era ghost town.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

A 140-year-old castle with underground caves hidden in San Francisco.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

It should come as no surprise that the best view of the Hollywood sign is from Batman's lair.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

Try not to get slimed in Tribeca.

A hand-built folk art installation covered with messages of God's love.

Site of a former hidden treehouse in New Orleans.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Eighteen miniature death-scene dioramas.

An enormous, inside-out glass globe built in 1935.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

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

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

The ghostly remains of an accidental sea.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

Remnants of a storybook amusement park hidden behind a strip mall.

A snapshot of the city's fascinating voodoo culture.

The old Niles Canyon Aqueduct in the San Francisco Bay Area is a bemusing and secret trail through nature for wayward travelers.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.