Cat art as far as the eye can see.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

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.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

Looming communist pillar with a Czech twist.

Macabre astrological automaton clock dating to the late 1400s.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

A former imperial sea-fortress and Soviet prison.

An empty relic of the Moscow Olympics crumbles away in Estonia's capital.

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

This one-of-a-kind archeological site is home to strange prehistoric ruins, the original use of which is still a mystery.

The first American department store, and home to the largest operating musical instrument in the world.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

The legendary building that needed ghostly approval before being built.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The land is home to swimming ponies and a legendary 18th-century treasure.

Explore the complex ecology of this multifaceted nature preserve by riverboat.

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

A toweringly silly piece of modern art has been delighting locals since the 1980s.

An elaborate shrine dedicated to the four corners of the world unfortunately misses its mark.

A mocking tribute to the past and modern leadership of Prague.

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Climb inside an iron crystal magnified 165 billion times its normal size.