The deserted remains of a luxury hotel turned hospital ward.

This mountaintop observatory is home to one of the world's largest reflective telescopes.

Mysterious face-like images that appeared within an Andalusian house are surrounded by legends of the paranormal.

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

The lengthy skeleton of one of the tallest Spaniards of all time is on display in Madrid.

Jesus' footprints and the first catacombs in the world.

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

Charnel house at the foot of Mount Sinai.

An ancient ossuary in Rouen.

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

Thousands of well-dressed mummies below a monastery.

Structure built from the skulls of vanquished foes.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

The mystic whose incorrupt corpse still attracts the faithful.

The mysterious megaliths have enchanted and intrigued visitors for thousands of years.

This 1,300-year-old marker is one of the finest and most complete early Christian crosses in Scotland.

This small museum in a 17th-century building honors three iconic Scottish writers.

Islanders once used this dramatic, otherworldly landscape to hide their cattle from Viking raiders.

These mysterious religious carvings were once thought to be thousands of years old but are actually the work of modern eccentric.

The ruins of a medieval seminary some say is the oldest university site in Scotland.

What happened to the three lighthouse keepers who vanished from this place remains a mystery over a century later.

More stones than Stonehenge, all scattered within a windswept landscape sure to enchant 'Outlander' fans.

The heart of a Scottish legend had a centuries-long journey before reaching its final resting place.