Odd stone and concrete monuments in the "Poet of the Sierras" eclectic folly garden.

The abandoned personal amusement park of the King of Pop.

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

This UFO landing strip was created by a charitable Wyoming city that was worried about residents of Jupiter.

An academy where anyone can train in the exciting acrobatic sports of parkour and freerunning.

Neoclassical Revival mansion and set of horror cult classic Phantasm.

Spiral labyrinth hidden in the hills above Oakland, CA.

San Francisco Bay's ghost town.

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

A walk through the historic city center, under the streets of Seattle.

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

Remains of a Greek freighter trapped off of Rocky Point in 1961.

The remains of a 12th-century chapter house in Golden Gate Park.

Rusty industrial city full of oxidized distillation towers.

Radioactivity still cause for concern at this urban explorer's paradise.

Where a staggering 747 ships were constructed during World War II.

San Francisco's first World's Fair, dedicated to the wonders of California.

World War II-era Nazi compound nestled in the Santa Monica hills.

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

Deco Modern sculptures of the people of the Pacific, cast for the 1939 Golden Gate International Exposition.

One time home to turn of the century explosives, now hidden under the Bay Bridge.

Abandoned bridge hidden deep in the San Gabriel Mountains.

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

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