A lush indoor jungle fills this bustling Madrid transportation hub.

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

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

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

This small and often-overlooked museum holds some of Spain's finest artistic treasures.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

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

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

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

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

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

The morbid items in this small and hidden museum are not for the weak stomached.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

Commonly acknowledged as the only public monument to the Devil himself.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

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

This large, circular tomb is the final resting place of the first emperor of Rome.

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

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.

A hospital where antique dolls are given new life.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

Architectureal fantasy quarter of Rome.