Canton Zug's borders were mainly established by nature itself: the rivers Sihl and Biber, and the Höhronen ridge in the east; the Rossberg mountain in the south, and the Rooterberg mountain, and the Reuss in the west. Only the 87.5 km-long border between the cantons of Zürich and Zug is not naturally defined. With its 1580 m peak, the Wildspitz is the highest point in the canton. The lowest point in the north of the canton is at 388 m, at Rüssspitz () on the border, the confluence of the rivers Lorzen and Reuss.