Formerly the world's largest, this Willy Wonka-esque contraption runs 24/7.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

A regular looking rock with an unbelievable history.

This unusual three-way wooden foot bridge spans two rivers at once.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

Once the most densely populated place in the world, this island is now a ghost town.

An abandoned 1920s-era stretch of cabins now overshadowed by the 66 Motel.

This collection of neon icons is preserving Arizona's history, one sign at a time.

This collection of vintage signs reflects the long and colorful history of this Arizona town.

A gorgeous stone viaduct crosses over a bucolic valley.

A section of a historic wooden trestle viaduct is preserved next to the railway line it once carried.

This spectacular bridge is part of an abandoned train line that once connected Mallorcan capital to the southeastern coast.

The abandoned transportation hub hides within the Glasgow attraction it once served.

Known as the most scenic route in Sri Lanka, this train line is steeped in history and offers an unparalleled view of the country.

Where a railroad loops under or over itself to rise or drop more than 70 feet in a short distance.

The ruins of one of the first railroads in the U.S. lie hidden within a neighborhood cul-de-sac.

Spectacular mineral formations fill these caves, which have been used for everything from smoking meat to stashing illicit liquor.

A toweringly silly piece of modern art has been delighting locals since the 1980s.

Historic funicular railway, believed to be the shortest railroad in the world.

The legendary building that needed ghostly approval before being built.

A frozen oasis lies beneath the scorching New Mexico desert.

A scrap-metal sculpture recalls an infamous 19th-century camel.

A creek tumbles over a series of step-like rocks to create this scenic water feature.

This cliff-face port is considered a masterpiece of mining engineering.