Macabre astrological automaton clock dating to the late 1400s.

This Ukranian fortress is one of the best-preserved medieval castles in Europe.

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

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

This hidden fortress has been coined the "City of Ghosts."

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

This snug medieval lane is one of the narrowest streets in the world.

The European towns of Brașov and Râșnov each have proud signs reminiscent of the Hollywood sign.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

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

The geographical center of Budapest is marked with a 10-foot-tall stylized zero.

A museum dedicated to a secret military hospital hidden beneath a castle in Budapest.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

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.

This massive underground salt mine now holds a sci-fi theme park in its depths.

The silly symbol for an underground protest group is now scattered around the city.