One of the newest mosques in a city filled with thousands.

This stone in Lake Geneva was once the reference point used to determine altitude in Switzerland.

Home of the Large Hadron Collider and the birthplace of the World Wide Web.

This futuristic German television spire is actually the world's largest digital clock.

This 1920s Amsterdam neighborhood was built as a giant experiment in concrete construction.

A public urinal so pretty, it was declared a national monument.

In the days before house numbers, these colorful signs held clues about various buildings' purposes.

This Neolithic passage tomb forms part of a World Heritage Site.

An enigmatic monument to the Irish revolutionary who plotted an uprising against British rule.

This courtly monument celebrates an influential comedian who turned taking the piss out of the powers-that-be into an art.

This once-grandiose behemoth of a monument from the socialist era now sits quiet and closed up.

This space age health spa looks like a supervillain's lair.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

The metal leaves on this tree are engraved with the names of Holocaust victims.

The hallucinogenic center of the ancient world.

During the Soviet era, the spire of this longstanding church was used as a radio transmission tower.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

This interactive sculpture allows visitors to leave a message in case a friend passes by.

Vast stretch of tide-pools with a unique Moroccan charm.

The largest madrasa in Morocco once housed more than 900 students within its exquisite walls.

It took 40 years to build this Eden-like garden in Marrakech, later restored by Yves Saint-Laurent.

World's most expensive home.

A Zoroastrian funerary tower where excarnation rituals are carried out is threatened by the area's dwindling vulture population.

This enormous gold Buddha statue was hidden inside a stucco decoy for centuries.