This abandoned secret city is a crumbling wonderland of Soviet ruins.

A Belgian self-built tower inspired by the Bible and ancient civilizations.

A huge cathedral single-handedly constructed by one eccentric monk.

An old hill fort covered in over 100,000 crosses is a symbol of Lithuanian nationalism and beliefs.

What almost started out as a spite house became an eccentric's found object masterpiece.

Flamboyant architecture from the turn of 20th century.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

Welcome to the world's only museum dedicated to the Ukranian Easter egg.

The largest catacomb system in the world.

Padlocks cover this rickety footbridge with love.

When you've got to go, you've got to go.

The eerie burnt-out remains of a prominent building where 30 protestors lost their lives.

An Art Nouveau building covered in animal gargoyles and grotesques.

The deepest metro station in the world.

The spectacular Roshen Fountain show lights up the night sky all summer long, until it "hibernates" under the ice waiting for spring to come.

There is a mouldering Jewish cemetery hidden away in the capital of Moldova.

A naturally beautiful, seemingly bottomless deep blue spring.

This ominous Albanian fortress houses tanks and downed planes as a reminder of their victories over Western imperialism.

Gigantic water vessel, permanently grounded in Southern Albania.

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

Space-age monument to an early 20th-century uprising.

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

A pair of connected skyscrapers form this symbolic gateway.

Structure built from the skulls of vanquished foes.