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

Late at night, the bust of the "Dracula" actor was snuck onto the facade of this Budapest castle.

Tucked away near more famous landmarks lies a statue meant to symbolize the confluence and continuing development of human culture.

A museum in the childhood house of a medical pioneer.

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.

Museum dedicated to the terror regimes of Hungary.

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

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

The memory of the ancient unit of measurement of local builders.

The final resting place of the famous violinist, after his corpse was denied a proper Catholic burial for decades.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

A former plague hospital turned medical museum.

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

An overgrown and largely forgotten cemetery lies hidden within the outskirts of Amsterdam.

One of the largest legal spray spots in Hamburg.

Stone memorial that's said to predict the death of the pope and the site of the Cadaver Synod.

The studio built by fascists in the hopes of "reviving the film industry" with the occasional propaganda film opportunity thrown in.

Pilgrimage site for star-crossed lovers.