The large alpine municipality is located at the confluence of the Urbach and Gadmer streams into the Aare river. It includes the Urbach valley, the Gadmen valley, the Gen valley, the Wetterhorn mountain and the Gauli Glacier. Innertkirchen was created out of the Bäuerten (farming communities) of Grund, Bottigen, Wyler-Schattseite, Wyler-Sonnseite and the agricultural cooperative of Äppigen in 1834. The merger with Gadmen almost doubled the size the municipality. Gadmen lies in the Bernese Oberland with the Susten Pass on the eastern border of the former municipality. The municipal borders stretch from the valley floor, with an elevation of , up to the nearby mountain peaks at about . It is located on the border of the Canton of Bern with the Cantons of Obwalden, Nidwalden, Uri and Valais.