This ancient market is often referred to as the oldest shopping mall in the world.

A forgotten "city of water" underneath the famous Trevi district.

Charles Dickens was not a fan of the ghastly wall dressings in this 6th century church.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

One of the most important yet well-hidden museums dedicated to the history of medicine.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

This hill made entirely of ancient Roman jars was simply a garbage dump to the people of the time.

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

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

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

An abandoned Roman salami factory has found new life as an art space home to 200 squatters.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

This delightful little museum is dedicated to only one thing: pasta.

Dedicated to the "father of modern education," this museum documents the history of education in Czechia.

A massive, abstract lookout tower providing a panoramic view of Prague.

An existential riddle in the world's largest ancient castle.

An eerie, existential museum dedicated to the author of "The Metamorphosis."

Walk through Czech history in Prague's largest graveyard.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

The risqué mixed-media sculptures are supposedly a metaphor for Czech politics.

This bar and museum are devoted to the controversial comic book work of Kája Saudek.

Germany has its very own Centralia, whose spark remains attributed to "spontaneous combustion."