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Watched a lot of distracting stuff on YouTube lately? Been walking around unencumbered by the debilitating reality of your own mortality? This'll fix that.

Kapilica Czaszk, or the Chapel of Skulls in Kudowa-Zdrój, Poland, is a beautifully macabre collection of cranial remains. The walls of this tiny church, built in 1776, are lined with the skulls and bones of 3,000 people. In the basement are the mixed-up skeletons of 21,000 more. All died in the 17th and 18th centuries, from causes as varied as the Thirty Years' War, plague, and syphilis.

Czech priest Vaclav Tomasek and grave digger J. Langer spent 18 years from 1776 collecting, cleaning, and assembling the human remains. After Tomasek himself died in 1804, his skull was placed on an altar in the center of the chapel.

Visit Atlas Obscura for more on the Chapel of Skulls.

Cranial wonders around the world:

• Hallstatt Charnel House is filled with hundreds of intricately painted skulls
• Skulls Unlimited: the place to go for all your skull-cleaning needs
• The Skull Tower of Niš is built from the heads of vanquished foes

Visit Atlas Obscura for more on the Chapel of Skulls.