A manifestation of modernist architectural ideas, this massive, multi-purpose building was one of the first of its kind in Southeast Asia.

Art and a pun, all in one.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

This cavern was used as a hidden hospital and safe house during the Vietnam War.

The first museum in the world devoted to sexual gadgetry.

A museum dedicated to the classic Italian scooter in the heart of Serbia.

The city of Manchester quietly unveiled this tribute to a 19th-century massacre.

Manchester's abandoned train depot lingers in a post-industrial purgatory.

Manchester salvaged this sculpture of the adopted Mancunian when it was no longer wanted in Ukraine.

A Victorian Gothic masterpiece housing a world-class collection of rare books and manuscripts.

Spain's stunning solar energy plant.

This Arab fortress was once the largest citadel in Western Europe.

Countless stories attempt to explain Poland's mysterious J-shaped trees.

In northeastern Poland, the ruins of a massive granary overlook the Narew River.

This abandoned Slovenian military barracks has become a punky-political art squat.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

This spherical sculpture has also been dubbed "the steel orange" due to its likeness to a massive, sliced piece of citrus.

The best-preserved ancient theater in the world.

An abandoned train station in Munich constructed for the 1972 Olympic games.

A small square plaque marks a failed assassination attempt that could have changed history.

This century-old cinema house has a marquee that has been hand painted by a single man for over 25 years.

A fearsome dragon clings to a corner of Munich's city hall.

This underground transport hub doubles as an art gallery.