Three bridges and one giant canyon make up this fantastic Spanish settlement.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Abandoned railway line circling the city of Paris.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

On the wall of this medieval walkway, a symbol of the Spanish Inquisition.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

A once grand hotel now sits eerily abandoned in the Catalan countryside outside Barcelona.

One of Europe's largest supercomputers is housed inside of a disused chapel.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

A beautiful but toxic fountain of mercury.

A statue dedicated to the founders of communism.

The ruins of the second-largest circus school in the world.

This medieval citadel once guarded the western entrance of the Pamir Highway.

The first version of this stalwart construction appeared around 3,000 years ago.

The world's second-tallest flagpole stands proud despite dropping rank.

A building facade covered with the statues of 11 giants of Tajik literature.

The heartbeat of modern Uzbekistan’s thriving market culture.

Touching displays of wishes for peace from the Cold War era.

Looking for a unifying history, Uzbekistan finds its answer in a 14th Century Turco-Mongol conqueror... despite the fact he wasn't Uzbek.

Giant cauldrons overflow with Uzbekistan's favorite rice dish at this cavernous dining hall.

An abandoned Soviet-era mining town in the mountains of South Kazakhstan.

A Stalinist prison camp for the wives and children of men accused of betraying the Soviet state is now a memorial museum.