One of the oldest, well-preserved water treatment facilities in all of Europe.

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

Enormous sandstone towers loom within a Czech forest.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

Two stunning 17th-century libraries and a cabinet of curiosities.

The final resting place of more than 200,000 people, this is one of the largest cemeteries in Europe.

This biographical museum honors the groundbreaking scientist at her birthplace in Warsaw.

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

A national collection of Communist-era musical posters.

This 700-year-old structure is one of the most unique architectural and historic monuments in Gdańsk.

Warsaw's fantastically preserved gasworks...almost.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

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

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

This cheeky restaurant has a serious devotion to lard sculptures.

A fortress built to pacify local uprising that had a stint as a Nazi concentration camp before becoming a five-star hotel.

This oddly shaped building is a surprising Soviet-era crematorium.

The largest catacomb system in the world.

The largest art park on the European continent.

Mostly underground in the old days Back in the USSR, today the Beatles beckon to tourists from a wall sculpture out in the open in central Russia.

Pictures tacked onto trees remember the more than 40,000 of Stalin's victims buried here in mass graves.

An art museum inside an active factory.

A small and surprising passageway in Saint Petersburg devoted to the Beatles.

The world's tallest statue of a woman wields the world's tallest sword and is at risk of toppling over.