The remains of this 2nd-century Roman temple are incorporated into a modern building.

A massive marble foot is tucked away in a small alley near the Pantheon.

A whimsical European-style chateau that calls the coast of Chile home.

You can spend the night in Dr. Frank-N-Furter's castle.

Numberless clock creates a meal of time for the dreaded, insectile Chronophage.

Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.

J.R.R Tolkien, C.S. Lewis, and other "Inklings" met at the Oxford pub to discuss the now legendary fantasy stories they were writing.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

Catacombs turned marketplace.

One part local history, 99 parts gruesome haunted house.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

In the fictional world of Kcymaerxthaere, celestial wonders marked a portal to a powerful route of travel at this site in Madrid, Spain.

This cafe offers a curated collection of treats and tipples made by monks and nuns.

A lush indoor jungle fills this bustling Madrid transportation hub.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Turntable anonymously received orphans, alms, and groceries.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

The ruins of an ancient stadium that hosted gripping chariot and horse races.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

Named after a lodging site that existed nearby, a bridge has existed at this location since 1455.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Local legend says Isaac Newton built this footbridge without any screws, bolts, or nails.