The Bauhaus-style former industrial complex is considered the world's most beautiful coal mine.

Decorated with a staggering 1,380 ladybugs, the installation has turned what was once a grim, forgotten nickel mine into a landmark and a statement.

A museum dedicated to secret surveillance.

What happens when you cross a mayor and a painter?

The elliptical citadel resisted the advance of the mighty Ottomans several times, thanks to the military prowess of the "Dragon of Albania."

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

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

This decommissioned nuclear power plant offers tours of its Communist-era control room and reactor hall.

A 90-ton, gravity-defiant steam locomotive shoots for the skies in this bizarrely beautiful public artwork.

A collection of old neon signs from all over Poland line a secluded courtyard.

The silly symbol for an underground protest group is now scattered around the city.

This obscene artwork on the side of a newspaper office pokes fun at a rival paper's former editor-in-chief.

One of the world's heaviest musical instruments towers within a popular urban park.

One of downtown Berlin's last reminders of its Communist past.

Through the colossal entrance to this cave you'll find limestone tubs and an underground waterfall.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

The ruins of an abandoned medieval city where the last Byzantine emperor was crowned.

The Greek War of Independence was declared at this medieval Byzantine sanctuary.

A magical, if a bit tacky, 1960s castle conjures up medieval fairytales and Greek mythology.

The historic tower houses of this nearly abandoned Greek town have been compared to the spikes on an iguana's back.

This town named for the ancient God of War is home to fewer than a thousand people, but it's the birthplace of the Greek Revolution.

This wrecked ghost ship has been rusting on a Greek beach since the 1980s.

340-foot statue built to honour the Heroes of the Soviet Union.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.