Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

A star-shaped fortress town fort built in the geometric model of the Renaissance utopian city.

A nature and cultural preserve named for its multitude of petroglyphs carved by the Northern Sinagua people.

This isolated island is often capped by its own fluffy cloud.

The giant statue and its model solar system honor the native Pole who declared that the Earth revolves around the Sun.

The discovery of an old wall led to the creation of this fascinating museum about the city in the Middle Ages.

In Portugal, a secluded stretch of untouched natural beauty hides at the bottom of a steep hill.

Austria's 5-star prison.

This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

This centerpiece of the Hollywood & Highland shopping center is a recreation of a long-lost movie set.

Iceland's tribute to its thankless civil servants.

The largest fountain in Bratislava.

These barriers stand as stark reminders of Northern Ireland's troubled past.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

In Northeastern Iceland lies something of an oxymoron: a steaming desert.

The cave holds a spectacular array of stalactites and stalagmites, including one shaped like a giant human heart.

This poignant sculpture of a gnarled weapon is a symbol of non-violence.

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

A small but hugely whimsical theater where marionettes play out the "The Battle of Stalingrad."

A museum glorifying the life of Stalin, located in the city of his birth.

This neon lit Georgian cave claims to hold the boulder Prometheus was chained to.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

These Stalin-era industrial 'death traps' hang lifeless above the city