An autonomous republic of Orthodox monks.

Celebrated example of Ottoman architecture that also served as a site for brutal massacres.

Oriental bazaar in the heart of Sarajevo.

These warring psychedelic crags commemorate an unsuccessful military operation.

A tiny church on a man-made island in the Adriatic.

A curious little museum dedicated to the furry feline in the cat haven that is Old Town Kotor.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

The unusual sculptures are believed to be powerful political symbols.

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

This 15th-century Serbian Orthodox monastery also contained a school for illuminating manuscripts.

Stone age urban planning.

The interior of this Serbian royal family's mausoleum is covered with exquisite mosaics.

In the hinterlands of Serbia's capital, a giant reflective mushroom houses an aeronautical history of the former Yugoslav republic.

A misnamed well, with a deep dark past.

Abstract monuments express sorrow and resilience at the site of a horrific massacre in Nazi-occupied Serbia.

A pair of connected skyscrapers form this symbolic gateway.

Structure built from the skulls of vanquished foes.