Map Dufour (FR)

The Dufour Map is the name given to a 1:100,000 atlas on Swiss territory based for the first time on precise geometric measurements. The project, which consisted of 25 plates of 70 x 38 cm, was carried out between 1845 and December 1864 by Guillaume-Henri Dufour, Swiss topographer and general. The projection used was equivalent conical projection. The reference point for altitude was the Niton Stones, whose elevation at the time was estimated to be 376.2 meters above the sea.