Stockholm's narrowest alley is barely over two feet wide.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Stockholm's deepest subway station is also a stunning ecological wonder.

The library's graceful rotunda is like a bibliophile's temple.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

This park built on a former fortress has a reputation for romance.

Take a seat and hear a song by the composer Frédéric Chopin.

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.

The Guardian of Tallinn.

Estonia's largest creative city is a vibrant bohemian hub located within a former industrial complex.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

"There's nothing there," and other lies the KGB told us.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

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

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Cold war icon and onetime "hole" in the iron curtain.

Home to 10,000 medical specimens including the remains of Rudolf Virchow's extensive collection of pathological specimens.

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

A fascinating insight into daily life in the Eastern Bloc.

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

The most visited, and possibly most controversial, museum in Germany.

This taxidermy scene brings the struggle for survival in the Indian jungle to a quiet corner of a Manhattan museum.

This morbid scene depicts the Darwinian drama of death on the African savannah.