A tiny wilderness cemetery commemorates the deadliest episode of the Klondike Gold Rush.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

An abandoned aircraft sits submerged in a lake in the Alaska wilderness.

The remains of a British railway rusting in the jungle mist of a Brazilian mountainside.

The experimental test tracks of a retro-futuristic monorail still stand in the French countryside.

Six times a day a train runs right through the middle of this Thai street market, sending vendors scrambling.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

This innocent-looking townhome is actually a subway exit.

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

Hear the tales of New York's most notorious criminals.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

The second tallest railway trestle bridge in America.

The spur that wouldn’t die.

A sliver of nostalgia in Seattle's Viretta Park.

The site of the Wellington avalanche, one of the America's worst railroad disasters.

This famous bridge twisted itself into oblivion, but not for the reason you might think.

The strange phenomenon causing gravity to "work backwards" on this hill has been blamed on the paranormal.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

A whimsical village of unique treehouses resides in a Washington forest.

This long, dark tunnel is open to hikers, but those without lights are known to get confused even on the straight path.

An abandoned network of military bunkers and tunnels open for anyone willing to descend into the darkness.

The industrial monstrosity known as Bagger 258 is a colossal mining machine built in the DDR - but now left for dead in a German field.

Stunning Roman aqueduct used for 1900 years and still standing.