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

100 year tradition of fist fights, marked by marble footsteps.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

A Nesting Doll of Churches.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Pompeii's less famous neighbor is still revealing her secrets.

Ancient snack bar of the Roman Empire re-opened.

Erotic art covers the walls of the largest ancient pleasure palace.

A floating cat sanctuary on an Amsterdam canal.

Across the Pacific in a raft, a museum dedicated to Thor Heyerdahl's now legendary expedition.

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

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

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

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

Elaborate tile work in this railway station tells the story of Portugal.

Romania's triumphal arch looks out over Bucharest.

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

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.