One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

The Guardian of Tallinn.

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

An abstract monument to a symphonic composer.

A subterranean house of worship carved right out of the bedrock.

Once a train station along the Great Eastern Railway this vibrant coffee shop and bar is where members of London’s creative class mingle.

London's smallest police station is barely the size of a phone booth.

The curios of pharmacist and collector Henry Wellcome.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

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

The prototype for all Nazi concentration camps.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

Real bones which are said to have belonged to a Polish dragon.

Museum celebrating the achievements of the Soviet space program.

Gargantuan home of Russian science.

Moscow's imposing monument to the Space Age.

The tallest hotel in Europe.

Moscow's most popular cemetery includes the graves of numerous cosmonauts.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

A sculpture park of the tossed aside relics of the USSR, from Stalin to a massive Soviet emblem.

A model village fit for an emperor.

An 18th century wonder of the world, lost in WWII, re-created at the Catherine Palace.