Once America's longest-manned military fort, now an abandoned hulk.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

Try not to get slimed in Tribeca.

This railroad magnate's 19th century tower is more than a little bit out of place in the Nevada desert.

World's largest collection of serial killer artwork and other macabre exhibits.

A self-built castle made by a mysterious man.

Tenacious mummies survived dental problems, eternal entombment, and more than their fair share of devastating fires.

A burnt orange monolithic dome structure perched on a hillside near Interstate 280.

Abortion, prohibition, religion, war, and fear all play a part in the history of this idiosyncratic Pacifica castle.

A castle that was built stone by stone by an eccentric journalist.

Forgotten and then destroyed by fire, this was once one of the largest saltwater swimming pools in the world.

An "anarchical" no man's land, complete with garbage sculptures and a hobo-run "Landfillian Library."

The home of one of California's most important horticulturalists wilts amidst a lovely park.

Storybook cottage in Beverly Hills was once the site of 1920s silent film studio, affectionately known as "The Witch's House."

An eccentric garden of sculptures crafted in India decorate an Irish green space dedicated to Alan Turing.

A French chateau, failed utopian community, odd museum, and Stonehenge replica in rural Washington State.

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

An abandoned castle owned and ignored by Masons carries a cursed history.

The former Naval shipyard is open for exploring - mostly.

The bones of an old zoo crumbling in the shadow of a new one.

A long abandoned hospital building on the outskirts of NYC.

A once grand hotel is being retaken by the wilderness it once capitalized on.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

One of the ghostly stops along Route 66.