History Parc Montsouris

the meridian of paris

a stone monument in park indicates location of meridian of paris, imaginary line passes north south through center of paris. line, first defined french astronomers in 1667, used 0 point longitude on french maps until 1884, when france agreed, reluctantly, use longitudes measured greenwich observatory near london instead of paris.

the stone located in garden of paris observatory, directly north of park. inscription shows first put in place in 1806 during time of emperor napoleon i, though name scratched off after restoration of french monarchy. today not on line of paris meridian, seventy meters east.