One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

The fountain marks the area where hundreds of accused witches were burned at the stake.

One of only two remaining Victorian-era greenhouses in New York.

Tucked in a nondescript downtown Brooklyn mall is a bar containing a remarkable turn of the century anatomical wax collection last seen in 1920s Berlin.

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

According to local folklore, this Roman sepulcher was once a throne for the Devil.

A burial vault located under Tiber Island in the middle of the Italian capital.

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

Jesus' footprints and the first catacombs in the world.

The final resting place of the poets Shelley and Keats.

The underground sanctuary of a mysterious ancient cult.

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

An alchemist's "magic door" stands in the middle of a Roman park.

A subterranean display of public art and architecture.

A delightful but little-known public observatory and planetarium in Munich.

One of the most easily accessible examples of the rare 1960s UFO houses.

The footprint of a frustrated devil in Munich's Cathedral.

The patron saint of spinsters grasps a container of dried blood.

A giant interactive periodic table with real samples of the elements.

One of the famous Czech artist's lesser-known Prague installations appears to be a glowing fetus affixed to a drainpipe.

This spooky statue sits outside a famous Prague theater.

A surreal statue honoring Prague's favorite literary son.

A series of playful yellow penguins share a serious message about the environment.

A sculpture of the iconic East German car on four legs is a tribute to those who traveled to Prague seeking asylum.