Lenk is the highest municipality in Simmental. The municipal area includes many mountains, the highest of which is the Wildstrubel (). Somewhat below the Wildstrubel, by the Siebenbrunnen (seven fountains) comes the Simme River, which gives Simmental (Simme Valley) its name. A number of creeks flow into the Simme, and the Iffig Creek, the Iffigfall (its waterfall), and the Iffigsee (its lake) are attractions for hikers. Other mountains nearby include the Wildhorn (3248 m) and Niesehorn (2776 m), commonly reached via trekking routes that begin in Lenk.