Steadily reminding Czechia of its past.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

An isolated, rusty phone booth commemorates Iceland's first international telegraph cable.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

This open-air museum was originally a World War II testing ground for German missiles and rockets.

This mysterious and once-grand memorial still embodies a remarkable architectural vision.

What was once an underground Nazi city is now Europe's largest bat reserve.

A mysterious structure left behind on the Polish mountainside, sometimes called "Hitler's Stonehenge".

An abandoned Nazi explosives plant founded by the inventor of dynamite is now an underground museum.

The site of the first battle of World War II.

A small monument in Lithuania marks the geographic center of Europe—or at least one of the claimants.

Launch site for nuclear war against Western Europe.

Spend the night in 1920s Latvia in this historic recreation and movie set.

Remains of the old fortification along the Western border of the USSR, now an elaborate defense museum.

A vast and unlikely aviation museum kept alive for over 50 years due to one man's tenacity.

Guests become prisoners on a visit to Latvian prison.

A top secret Cold War bunker hidden beneath a Latvian spa facility is now open for tours.

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

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

Budapest's Communist-era statues, banished to the suburbs.

The abandoned "Red Star Train Graveyard" is the final rusting place for precious artifacts of train history.

Museum dedicated to the terror regimes of Hungary.