Abandoned Nazi train station turned underground astroparticle laboratory.

Sanctuary on a ridge near an ancient shrine to a "Black Madonna" built by the founder of Opus Dei.

In one of the smallest countries in the world stands an original Salvador Dalí sculpture.

Long tunnels run under the ancient chariot racing circuit to the tower.

This Roman arena once played host to bloody gladiatorial battles.

Touching the iron railings of Tarragona's balcony to the Mediterranean is said to bring good luck.

Stunning Roman aqueduct used for 1900 years and still standing.

This magical space partly designed by Antoni Gaudi is one of the best examples of romantic gardening in the Mediterranean.

The ruins of a bombed medieval village memorialize the destruction of the Spanish Civil War.

These ruins are all that remain of Tortosa’s lost coal gas manufacturing industry.

This memorial, built by fascist dictator General Franco in 1960, has been repurposed by the people of Catalonia.

This Canadian hunting lodge is a long way from home.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Built as a gift to the hottest tastemaker of the time, these hidden quarters remain an Art Deco showpiece.