Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

This dazzling Art Nouveau mansion is now home to the Modern Art Gallery Subotica.

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

The unusual sculptures are believed to be powerful political symbols.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

A two thousand year old brothel uncovered in Northern Greece.

After being destroyed by two separate fires, this monastery is now home to a small zoo and relics from dozens of saints.

A seaside castle complex that stood through centuries of conquests.

An early 20th-century bullring converted into a modern shopping center.

Mountain where Jesus was first tempted by the Devil.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

The mark of the Devil's horns on a marble column in Milan.

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

Old batteries and frog skeletons reside in this lakeside monument to Alessandro Volta.

The ruins of a military-industrial complex now host concerts and more.

These unique sculptures form a musical ensemble of recycled metal.

This exclusive resort has completely covered a tiny Balkan island in a 5-star warren of guest rooms.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

It's good luck to be mocked by this monkey.

The great Danube river starts here.

A Black Forest cuckoo clock theme park features one timepiece big enough to walk inside.

This medieval cathedral houses stained-glass windows featuring saints and pretzels.

A stonemason's hilarious revenge came in the form of this peculiarly positioned gargoyle.

Visitors dating back to the 1600s carved their marks in the stones of the iconic tower.