A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Houses are tucked between, on, and underneath giant boulders.

A submerged village appears when dam levels drop.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

Buildings from the fictional planet of Tatooine still litter the Tunisian desert.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

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

The ruins of an ancient stadium that hosted gripping chariot and horse races.

A 16th-century Andalusian palace.

This former charity hospital for elderly clergy houses some of Seville’s most treasured paintings.

The final resting place of the great navigator, or maybe his brother.

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

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

God's Saharan sandbox of wrath.

This town named for the ancient God of War is home to fewer than a thousand people, but it's the birthplace of the Greek Revolution.

Seventeen oak trees sprout from the roof and walls of this tiny chapel without any visual evidence of roots.

The historic tower houses of this nearly abandoned Greek town have been compared to the spikes on an iguana's back.

This 15th-century island fortress later served as home to the executioners no one wanted to live near.

The largest and most famous wax anatomical collection anywhere in the world.

Five ancient libraries, little changed for centuries, preserve a medieval archive of Quranic lore and civic documents

It's hard to believe the dizzying patterns covering this abandoned mine are completely natural.

Take respite inside this jaw-dropping church while climbing the volcano where Georgia's Prometheus was once chained.

This ancient village and its adjoining cemetery have a beautiful history of death and remembrance.

The Neapolitan Cult of the Dead still cares for the skulls at this mini-Fontanelle.