{"$schema":"https://proj.org/schemas/v0.7/projjson.schema.json","type":"ProjectedCRS","name":"ATF (Paris) / Nord de Guerre","base_crs":{"type":"GeographicCRS","name":"ATF (Paris)","datum":{"type":"GeodeticReferenceFrame","name":"Ancienne Triangulation Francaise (Paris)","ellipsoid":{"name":"Plessis 1817","semi_major_axis":6376523,"inverse_flattening":308.64},"prime_meridian":{"name":"Paris RGS","longitude":2.33720833333333}},"coordinate_system":{"subtype":"ellipsoidal","axis":[{"name":"Geodetic latitude","abbreviation":"Lat","direction":"north","unit":{"type":"AngularUnit","name":"grad","conversion_factor":0.0157079632679489}},{"name":"Geodetic longitude","abbreviation":"Lon","direction":"east","unit":{"type":"AngularUnit","name":"grad","conversion_factor":0.0157079632679489}}]},"id":{"authority":"EPSG","code":4901},"remarks":"ProjCRS covering all mainland France based on this datum used Bonne projection. In Alsace, suspected to be an extension of core network based on transformation of old German system."},"conversion":{"name":"Nord de Guerre","method":{"name":"Lambert Conic Conformal (1SP)","id":{"authority":"EPSG","code":9801}},"parameters":[{"name":"Latitude of natural origin","value":55,"unit":{"type":"AngularUnit","name":"grad","conversion_factor":0.0157079632679489},"id":{"authority":"EPSG","code":8801}},{"name":"Longitude of natural origin","value":6,"unit":{"type":"AngularUnit","name":"grad","conversion_factor":0.0157079632679489},"id":{"authority":"EPSG","code":8802}},{"name":"Scale factor at natural origin","value":0.99950908,"unit":"unity","id":{"authority":"EPSG","code":8805}},{"name":"False easting","value":500000,"unit":"metre","id":{"authority":"EPSG","code":8806}},{"name":"False northing","value":300000,"unit":"metre","id":{"authority":"EPSG","code":8807}}]},"coordinate_system":{"subtype":"Cartesian","axis":[{"name":"Easting","abbreviation":"X","direction":"east","unit":"metre"},{"name":"Northing","abbreviation":"Y","direction":"north","unit":"metre"}]},"scope":"Engineering survey, topographic mapping.","area":"France - Alsace.","bbox":{"south_latitude":47.42,"west_longitude":6.84,"north_latitude":49.07,"east_longitude":8.23},"id":{"authority":"EPSG","code":27500}}