Portugal plays host to several bone chapels that are located across the country. Just behind a church in Alcantarilha, sits one of the country’s more hidden chapel of bones. 

Inside the 16th-century chapel, the remains of an estimated 5,000 skeletons make up the walls, ceiling, and even the altar. You’ll usually have the chapel all to yourself—an unusual feature of most bone chapels in Portugal. It makes for an intimate, yet macabre experience.