A pair of connected skyscrapers form this symbolic gateway.

A Serbian church lit by chandeliers made of weapons.

This memorial park stands on the site of one of the largest mass executions of the Second World War.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

Structure built from the skulls of vanquished foes.

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

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

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

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

The largest Roman amphitheater in the Balkans once held over 20,000 people, but managed to lay hidden for hundreds of years.

Bronzes and busts that once stood in the city's main squares are now relegated to a small hidden courtyard.

Once the fallout shelter of a dictator, this sprawling bunker is now a combined history museum and contemporary art gallery.

An Albanian monument to the Communism that nearly crushed the country is now a crumbling wreck.

This 135-year-old weather station studied the effects of the climate on human health.

The big toe of this towering monument to a Croatian national hero is worn from years of superstitious rubbing.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

A musical instrument played by the sea.

This one-time health resort was used by aristocrats around the world.

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.

A whimsical bridge adorned with decorative dragons.

This abandoned Slovenian military barracks has become a punky-political art squat.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

In Egypt's expanding metro area, many of the neighbors are dead.

This ancient structure is widely thought to be the oldest intact pyramid in the world.