Constructed for defense, this fort oversaw the dress rehearsal for one of the largest invasions in history.

This chapel was built by Afonso de Albuquerque in 1510 to commemorate his entry into the city of Goa on St. Catherine’s Day.

Though they look like Hobbit houses, these semi-underground stone structures were built for winemaking.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

This sculpture presents commentary on a life in pursuit of profits.

This unique bridge curls up like a caterpillar to let boats pass and then unfurls again to span a small canal.

An abandoned saucer-shaped monument in the Bulgarian mountains.

An enormous Soviet aircraft, the only one of its kind, stands at the deserted shore of the Caspian Sea.

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

The only residents of this abandoned housing development full of identical castles are stray cats and dogs.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

Granny Smiths and Fujis can both be traced back to Kazakhstan, where apples still grow wild.

This village was once a thriving Soviet uranium mining center, but is now semi-abandoned and desolate.

Now overgrown, these anti-tank barriers from World War II are sometimes called "dragon's teeth."

Huge concrete structures designed as an early warning system for Britain to detect enemy aircraft.

Former island in the Aral Sea used to be a top-secret Russian bio-weapons facility.

This abandoned Brutalist treehouse is a hidden architectural relic.

A gigantic sculpture garden is packed with innovative oddities.

This beautiful natural train tunnel is said to grant the wishes of visiting lovebirds.

This massive chapel in the middle of the Indonesian forest is both haunting and fowl.

The haunting peak of an old church is all that remains of a drowned Brazilian city.

An abandoned Santa park is as far as this proposed theme park kingdom got toward completion.

The rocks in this arid basin leave trails of movement behind them.