The remains of what was once the world's steepest passenger funicular.

A ruined mansion hidden in the woods of the Hudson Valley, home of a tragically doomed romance.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

It would take 35 firetrucks to fill this enormous glacial pothole.

100 massive sculptures in the Hudson River Valley.

Six peaceful acres in a residential neighborhood dedicated to art and peace.

Non-profit time travel mart sells goods you would need for a trip through the fourth dimension.

A psychedelic labyrinth on the San Francisco bay.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

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

A toxic ghost town sitting atop a massive coal fire.

A recently abandoned psych ward at the end of Sanatorium Road.

An enormous overgrown greenhouse teeming with graffiti and wildlife.

This hospital fell into ruins after failing to act as the advocate for the mentally ill it was designed to be.

Hidden deep within New Jersey Pine Barrens is a massive graffiti wonderland.

This unassuming retro burger joint was billed as “diner of the future” at the 1939 World's Fair.

An unusual assortment of steerable wooden sleds is on display in a library in New Jersey where they were first invented.

A unique sculpture park that specializes in the huge and bizarre.