A striking symbol of the Bulgarian capital.

Depending on the region's rainfall, this church may be partially submerged.

A futuristic, brutalist masterpiece that is also strangely prison-like.

This massive monument was unveiled the day Kosovo declared independence from Serbia.

An unfinished Serbian Orthodox church with 1,389 golden crosses planned to represent the Battle of Kosovo.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

This easily overlooked memorial immortalizes the scars from the 1956 Hungarian Revolution.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

Some call this eerie forest of crooked trees the "Bermuda Triangle of Romania."

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

This 13th century Orthodox monastery is built right into the Moldovan cliffside.

This abandoned Soviet circus is slowly being restored to its Communist-era glory.

A tiny town hall—in Sweden's one-time capital—might be the smallest in Europe.

Sweden's oldest street has not changed for nearly a millennium.

Now a hotel, this former bank was the site of a robbery that spawned a psychological phenomenon.

An ancient Viking runestone hidden in plain view in Stockholm's old town.

Several cannonballs of mysterious origins decorate two buildings in Stortoget's main square.

Stockholm's narrowest alley is barely over two feet wide.

The site of the first battle of World War II.

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

Inside this Krakow church, an explosion of psychedelic color.