A tiny replica of the iconic London landmark hides on the side of the steel structure.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

This obscene artwork on the side of a newspaper office pokes fun at a rival paper's former editor-in-chief.

Berlin's old airport.

The skeletal frame of a decommissioned gas-pumping station offers breathtaking views of greater Berlin.

Berliners converted a bombed-out, disused lot into a community-run urban farm with its own cafe and bar.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

A restaurant and observation deck built in a unique broadcasting antenna.

The world's first motorway was used as a racetrack until the late 1990s.

An imperial church bombed to ruins during WWII now stands as a jagged memorial.

Metro station with a claim to rock n' roll fame.

A museum dedicated to the former country.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

In the hometown of the Catholic saint and Nobel Peace Prize winner, a memorial dedicated to her legacy.

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.

A marvel of Byzantine engineering under the streets of Istanbul.

Taking the subway here means doing so over a bridge located in the middle of an estuary.

The legendary luxury train passage is commemorated with a charming museum inside its former eastern terminus.

Ancient serpentine sacrifice holder that has stood the test of time.

A fountain standing as a testament to a doomed alliance.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.