A striking symbol of the Bulgarian capital.

A collection of art from Bulgaria's time as a communist state.

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

The first mosque in the world to receive electricity.

This enormous abstract sculpture is part jungle gym, part elaborate noise-making machine.

Some of the best-preserved specimens of the monumental medieval tombstones found throughout Bosnia and Herzegovina.

Place with alleged mystical powers in Old Orthodox Church in Sarajevo.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

Inat Kuća, or "House of Spite," is more than just an oddly named restaurant.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

Oriental bazaar in the heart of Sarajevo.

This historic cemetery was inaccessible for several years due to dozens of land mines.

The place where World War I began.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

A magnificent collection of imperial armor and weaponry.

The first modernist church in Europe.

The solemn exterior conceals an opulent interior of this 17th century church.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

A silly medieval mural preserved on the side of a Viennese house.

An exquisite Baroque church in Vienna's old town.

Legends surround an ancient tree trunk riddled with nails for good luck.

Baroque celebration of the end of the Great Plague of Vienna.