A 1,000-year-old church holds the bones of the Christian martyrs who died hiding inside it.

Venice's island of the dead.

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

Naturally preserved bodies are eerily staged throughout the crypt in varying poses.

This Italian pyramid is said to hold the mingled remains of the dead from both sides of the Battle of Novara.

The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

One of the largest ossuaries in Spain is packed from floor to ceiling with bones.

A house of bones — but nobody is quite sure to whom they belong.

Mysterious painted skulls in Moravia.

This German bone house contains the remains of some 20,000 souls.

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.

The mortal remains of an estimated 70,000 people lie in the basement of a monastery in Lima, Peru.

Europe's second largest ossuary wasn't discovered until 2001.

The name doubles as an appropriate adjective for this small ossuary.

A rare example of a German cemetery with traditional grave markers dating back several generations.

These jeweled relics have a scandalous and contested past.

These 17th-century mummies are no longer naturally preserved, but remain on display today.

In 1830, cemetery workers in Cham unearthed a chamber housing thousands of skeletal remains from the 13th century, which can still be viewed today.

The mystery of the Putim Ossuary involves a tricorn hat.

An Austrian house of bones filled with hundreds of intricately painted skulls.

Terrifically morbid cemetary and site of famous Paracelsus' grave.

The personal charnel house of Anton Bruckner.

In a small churchyard in Dingolfing, Germany the quaint Schusterkapelle is there to remind you of your imminent mortality.

Artfully arranged bones of 5,800 Austrians.