This remarkable prehistoric town is full of watchtowers and houses that have withstood thousands of years.

The Gaudí-inspired building that was the start of Terrassenc modernism.

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

The hidden ruins of an old hydroelectric plant reclaimed by nature.

On La Gomera, "Silbadors" communicate in a 4,000-word language of whistles.

This line of 12 tower mills described in the story of Don Quixote is among the most iconic landscapes in Spain.

Over 4,700 miles of trees being planted to hold back the desert.

Near the ruins of a Civil War coastal fortress lies the only known African refugee cemetery in the United States.

There is only one place in the world where the corners of four nations come together.

The true jewel of Africa's west coast known as "Africa's Last Eden."

The famous boat that once ferried Bogart and Hepburn still floats in Key Largo after being abandoned for years.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

Rolling sand dunes of the Sahara... in the middle of the Atlantic Ocean.

This ancient Spanish castle sits high upon a hilltop.

A medieval village holds a very modern hotel.

This enchanting natural park is a magical example of a temperate rainforest in Europe.

An eerie collection of the surviving structures from a past celebration of the future.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

"Alleys of Stone" form natural mazes in Spanish natural park.

Blue-green pools and smooth stones comprise one of Spain’s most idyllic hidden wonders.

Devastated landscape used for hundreds of years by the Romans as their primary mining site.

Mine shafts and hard pastries await visitors at this massive mountain of salt.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.