The Vercors Massif is a roughly triangular-shaped plateau with a maximum north-south length of and a maximum width of . The area is . The lowlands surrounding the steep-sided plateau average about in elevation above sea level while the top of the massif has an average elevation of about with a maximum elevation of at Grand Veymont. Unlike a flat-topped mesa, three ridges run along the top of the massif from north to south. Only a few roads climb the steep slopes to access the massif and the population lives in a few small villages. The porous limestone rocks and karst terrain result in an extensive system of caves and caverns and a scarcity of surface water in the form of streams, springs, and shallow wells. These characteristics would be important during the battle as the Germans took control of the water sources and ambushed maquis seeking water.