When the rain falls, this drain system turns into a musical instrument.

Blitzkrieg bop your way through Berlin's Ramones Museum.

Berlin's old airport.

A 12th-century fortress containing some of Berlin's oldest buildings.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

The secret medieval communication system will whisk your words above the noise of the crowd.

This giant middle finger statue sends an unambiguous message to Italy's bankers.

Small on the outside, big on the inside, this church is an astonishing act of visual deception.

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

Floating swimming pool within a moored vessel.

A fascinating insight into daily life in the Eastern Bloc.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

This imposing memorial contains the remains of Che Guevara — and 29 other guerrillas who died with him in Bolivia.

Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

This zoological museum began as the first great curiosity cabinet.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.