An extensive network of secret tunnels was created for the Nazi project "Riese."

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

Nearly three decades since the fall of the Soviet Union, the hero of the USSR still stands over Belarus.

Dozens of Soviet-era trains and carriages fill this outdoor museum.

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

Crosses of all shapes, sizes and colors litter the mountain, the site of a huge yearly Orthodox pilgrimage.

This wooden mosque is one of the few remnants of medieval Poland's Muslim Tatar community in this deeply Catholic country.

A striking Soviet memorial commemorates the liberation of Belarus from the Nazis.

The centuries-old crosses "growing" in the cemetery are steeped in local lore and are believed to have healing powers.

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

The secret meeting held in this building would forever change the world.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

A monument in the Belarusian city of Polotsk claims to mark the exact midpoint of the European continent.

This striking structure is the Socialist-modernist centerpiece of a former Soviet spa resort.

Open-air museum with a large collection of Soviet-era statues.

A curious art park at the geographic center of Europe is home to 3,000 television sets and other wonders.

The oldest funicular in Lithuania has been climbing this steep hill since 1931.

You would never guess that before World War II this lonely field was a bustling German city.

An impressive ensemble of sculptures that survived the Soviet regime.

A small granite monument marks where the borders of three countries meet.

Once a giant gingerbread factory, this space now hosts exhibits and workshops on the historic treat.

An abstract and eyecatching clock/fountain is the centerpiece of this little-known German city.

This abandoned but well-preserved Prussian fortress sits abandoned in a Polish forest near the German border.

This giant, 83-year-old ship elevator is an engineering feat to behold.