The Catacombs occupies abandoned quarries located 20 metres beneath the ground of the city. It served as an alternative burial location when the city suffered from serious diseases and famine in the years leading up to the French revolution. Between 1785 and 1787, remains from various cemeteries were removed and then skeletons were sorted and neatly stacked according to type. The transfer of human remains from other urban burial sites continued until 1870s and the Catacombs became the final resting place of an estimated 6 million former Partisans.
Paris Catacombs is modelled after the Roman Catacombs covering a surface of 11,000 square metres, the labyrinth of corridors open to the public is 1.7 km long, but the collective reach of the networks of underground tunnels is approximately 300 km. To date, it is a popular tourist attraction which opens from Tuesday to Sunday (10am to 5pm, 4pm is the last admission) with a minimal entrance fee.
I visited Paris in September 2008 and the Catacombs is one of the must-see tourist attractions at the City of Lights!