Bold black and white motifs of life and death add a dramatic flair to this 17th-century crypt.

Legends surround this natural rock formation that looks like a Moorish king wearing a crown.

Down this yellow brick road, visitors are treated to toadstool houses and massive mushroom sculptures.

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

This abandoned viewing platform has become a monument to unnecessary government spending.

With a facade that measures just 107 centimeters, this five-story building is one of the skinniest in Europe.

A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

A replica of the Roman emperor in glorious full color.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

The world's most elegant power lines.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

The people murdered during a 17th-century Norwegian witch hunt have been honored with a pair of stark, modern installations.

The giant club-wielding wildman stands proud as the symbol of Swedish Lapland.

The ruins of this ancient fortification wall sit in the middle of a quiet, residential intersection.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

These caves secretly held national treasures during World War II.

This striking sculpture of Icarus honors Greece's fallen flyers.

Where commuters walk through remnants of an ancient Greek necropolis.

View the ancient remains of buildings and the ancient "River of Hades" before hopping on a train.