This vibrant side road in Doha was painted light blue to reduce heat.

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

This massive blockhead sculpture hides an entire library.

An Orthodox church built by the Royal Family for the Russian community exiled to the French Riviera.

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

A curious cave church carved into the face of a cliff.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

This legendary city has been a tourist attraction for centuries.

The hallucinogenic center of the ancient world.

Monasteries on rock pillars, once accessible only by frayed ropes.

This natural spa is known for its healing properties and vibrant hue.

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

Near Belgrade, an ancient-looking sarcophagus serves as a World War I monument.

A maze of underground tunnels beneath one of the most beautiful forts in Serbia.

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

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

Religious perseverance and cultural coexistence manifest in an architectural gem that multiple wars couldn't topple.

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

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

Structure built from the skulls of vanquished foes.

A whimsical bridge adorned with decorative dragons.

Two stone columns flank the grand Venice square, but there were supposed to be three.