Projected data in Lambert 1

During the initial phase of the Alpage project (2006-2010), the projection system in use at the time was the Lambert -1 coordinate system, specific to northern France. Since then, a directive requires all public administrations to produce georeferenced data in Lambert 93 (EPSG code 2154) in order to facilitate exchanges within the French space. The Alpage data that can be downloaded and displayed on the webmapping platform have therefore been converted to this 2154 system.
For archiving purposes, the first version of the data produced until 2019 is available here in Lambert 1. However, this old projection system will soon no longer be recognised in GIS software and we therefore strongly advise you to switch to Lambert 93.

Historical topography

Socio-economic activites

Spaces of power

Archaeological remains

Environmental dynamics

Ancient urban fabric

Paris in 1380