A war-torn Olympic relic is being overtaken by graffiti and nature.

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

Bridge that died in war and was resurected.

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

The apartment building where JFK's assassin lived after defecting to the Soviet Union.

Glowing orb in Minsk houses 8,600,000 items.

Thanks to its heroic service during WWII this Soviet castle has been turned into a monument towered over by a brutalist titan.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

The world's oldest known salt mine.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

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

Giant stone letters dedicated to the founder of Armenia's alphabet.

Nestled in a peaceful valley, this Armenian monastery may have been saved from Mongols thanks to the eyes of God.

The most visited pilgrimage site in Armenia once held a saint in a pit for 13 years.

Its humdrum facade only adds to its electrifying appeal: a rooftop with panoramic views of a shapeshifting metropolis.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

The building's fluid, wavelike walls are a true feat of architectural ingenuity.

A gigantic collection of teeny, tiny books.

A shrine of fire worship built on top of a natural flame.

Mysterious hillside with a continuously burning natural fire.