Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

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

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

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

A beautiful mountaintop mausoleum devoted to a Montenegrin icon can't seem to make everyone happy.

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

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

A solar-powered primary school inspires hope and experimentation in a country ripe for energy innovation.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Thousands of rusting train cars have been slowly falling apart on the edge of Greece's second largest city.

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

Structure built from the skulls of vanquished foes.

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

Serbia's master of striking memorials erected a forgotten, hidden gem in the hills outside a tiny village.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Bridge that died in war and was resurected.

On top of a resort town as old as the Bronze Age sits an incredible war memorial statue overlooking the beaches below.

The legendary cliffside castle of three-time Voivode of Wallachia, Vlad the Impaler.

This massive underground salt mine now holds a sci-fi theme park in its depths.

The ceiling of Prohodna Cave in northern Bulgaria affords a peek at the sky via two deity-sized-eye-shaped holes.

This cubist Vienna church building looks like some sort of alien stonehenge.

One of the largest barracks of the Austro-Hungarian monarchy's military is now an abandoned ruin.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

Artfully arranged bones of 5,800 Austrians.