Topographic Map of Switzerland

The Topographic Map of Switzerland (German: Topographische Karte der Schweiz), also known as the Dufour Map (German: Dufourkarte; French: Carte Dufour) is a 1:100 000 scale map series depicting Switzerland for the first time based on accurate geometric measurements. It is also the oldest official map series of Switzerland.

Source: Wikipedia — Topographic Map of Switzerland (CC BY-SA 4.0)