The peak of the Brienzer Rothorn (2350 m) marks the boundary between the three cantons of Bern, Lucerne and Obwalden. The Brienzer Rothorn is a lime formation that developed during the Cretaceous period. Its situation to the north of the Brienzersee (Lake Brienz) allows excellent views of the peaks of the Bernese Alps such as Eiger, Mönch, Jungfrau and Blüemlisalp.

The Brienzer Rothorn is reached by cogwheel steam railway from the Brienz side (summer only), Switzerland’s oldest cogwheel steam railway. Operating since 1892, the railway’s 15 kilometre ascent covers 1678 metres altitude. Most compositions are still driven by steam engines, including four newer engines operating since 1992 and 1996.

A cableway ascends the mountain from the Sörenberg side. This is the mountain terminus accessing the Eisee ski region in winter. 200 metres from the cableway terminus is the Berggasthaus Rothorn Kulm. Most hikers approach the Brienzer Rothorn from the east, coming from the Brünig Pass or Schönbüel, or the south, coming from Brienz. Both mountain hikes offer numerous views of majestic scenery. The steep ascent from the northern side via Sörenberg and the western approach along the Brienzergrat are more challenging and not as popular.

The Brienzer Rothorn is popular with nature lovers. Its proximity to the conservation area of the Augstmatthorn allows sightings of chamois and ibex and even golden eagles soaring overhead. Un-feathered early birds can spend the night at the Hotel Rothorn Kulm and watch the sunrise.