1513 Turkish world map, full of European state secrets and snarky commentary.

A marvel of Byzantine engineering under the streets of Istanbul.

The first mosque in the world to receive electricity.

This unusual hostel provides a glimpse of life in a city under siege.

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

Controversial site of what could be Europe's first pyramid.

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

This abandoned Olympic skiing facility still bears the scars of the Siege of Sarajevo.

This top-secret nuclear bunker hidden in a Bosnian mountain has been converted to a modern art exhibition space.

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

A former bank seized as a sniper vantage point during the Bosnian War is now a secret graffiti art gallery.

This surreal memorial/cemetery is a necropolis of crumbling stonework and puzzle-shaped headstones.

Carefully reconstructed after the Bosnian War, this 16th-century bridge stands as a symbol of the country's enduring multicultural heritage.

This picturesque monastery at the base of a cliff is a peaceful oasis open to all visitors.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

An ancient knight and a symbol of the city's freedom.

This 15th-century church houses priceless works of art from a range of Croatian artists.

Gargoyle head that brings good luck.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

This Croatian island is for sale but no one is buying due to the dozens of accused Nazi sympathizers who were massacred there after WWII.

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

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