An ancient Egyptian temple in the middle of Madrid, Spain.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

Infamous and now demolished panopticon prison built by its former inhabitants.

One of Madrid's oldest trees, with a long and colorful history, resides in El Retiro Park.

Remains of the lost church hide beneath this Spanish Parliament building.

A rare set of strings by famed instrument maker Antonio Stradivarius is on display in the Royal Palace.

A reproduction of the famous prehistoric cave paintings is hidden underground at the National Archaeological Museum.

This embalmed man is one of the best preserved mummies from the Canary Islands.

Part of the medieval watchtower is displayed in an otherwise ordinary parking garage.

This fascinating and poignant museum chronicles every imaginable aspect of Spanish colonialism in the Americas.

Stuck in the middle of a modern Madrid city block are the remains of a 19th century sports complex.

Just like in Hollywood, Madrid has also a forgotten walk of fame.

The remains of the second-oldest zoo in Europe can be seen within these library gardens.

This small museum tucked within a subway station holds pieces from Madrid's past.

Madrid's last horchata kiosk is a blue-and-white beacon of refreshment.

A subterranean relic of the Spanish Civil War hides below this picturesque park.

An iconic and controversial ancient Iberian funerary urn with a hauntingly penetrating gaze.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

An exact replica of a colossal Olmec head sits atop a pyramid within a Madrid traffic circle.

The little church's beautifully frescoed ceiling has earned it the nickname “the Sistine Chapel of Madrid.”

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.

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