The Catacombs of Paris are a vast network of underground tunnels and ossuaries located beneath the city of Paris, France. Originally limestone quarries, they were transformed in the late 18th century to house the remains of over six million people, as the city's cemeteries became overcrowded. The catacombs stretch for approximately 200 miles, but only a small section is open to the public. Visitors can explore the catacombs through a designated route that showcases the eerie yet fascinating arrangement of bones and skulls. The site serves as a reminder of Paris's history and the changing attitudes toward death and burial practices. It attracts tourists and history enthusiasts from around the world.