The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

The seamy, underground secrets of Portland's criminal past.

The final resting place of New Orleans' most famous voodoo priestess.

Venice's island of the dead.

The ancient tomb acts as a calendar that keeps perfect time.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Visible below the waves are memorials to the city's Gold Rush dead.