A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

The only museum with its curator—and her pets—buried inside.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Go inside to really appreciate this 500-year-old technological masterpiece.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

This one-time health resort was used by aristocrats around the world.

A triumphant marble and bronze fountain depicting a 15th-century Hungarian king and his hunting party.

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

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

Real bones which are said to have belonged to a Polish dragon.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

Beneath Kraków Old Town's main square lies a hologram-filled medieval market vampire graveyard wonderland.

Throughout this shopping mall are medieval ruins that were discovered during the mall's construction.

A surreal statue honoring Prague's favorite literary son.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

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

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

The hidden lair of an alchemist rediscovered in a 2002 flood.

Macabre astrological automaton clock dating to the late 1400s.

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