Dreisesselberg, Mountain summit in Bayerisch Gmain, Germany.

Dreisesselberg is a 1,664-metre summit in the Lattengebirge range of the Northern Limestone Alps, in Bavaria's Berchtesgadener Land district. The mountain is built of limestone, and the Steinerne Agnes rock formation lies southeast of the summit at about 1,300 metres.

The name Dreisesselberg refers to an old tripoint where the County of Plain (Salzburg), the Reichenhall court (Bavaria) and the Prince-Provostry of Berchtesgaden met. The boundary line was fixed around 1295 after the Plain counts died out in 1260 and Salzburg's succession was settled by the Second Erharting Treaty of 1275. The stretch stayed disputed until the 1851 treaty placed the state border at the Rötelbach in the Augustinergraben, about 3 km northeast of the Sesselberg.

The mountain's name refers to an old tripoint where the County of Plain (Salzburg), the Reichenhall court (Bavaria) and the Berchtesgaden provostry met; their judicial borders ran through this spot. The resulting wedge of Salzburg territory at the Spitz am Hallthurm controlled the road from Reichenhall to Berchtesgaden over the Hallthurm, today's B20, which mattered for salt exports and tolls.

Several hiking routes reach the summit, with options ranging from easier to more moderate difficulty. The paths are well-maintained and many sections pass through shaded forest areas.

The Dreisesselberg is not granite but part of the Northern Limestone Alps. Southeast of the summit, at about 1,300 metres, stands the rock formation Steinerne Agnes, a landmark many hikers pass without noticing. The mountain's name recalls an old tri-border point between the County of Plain, the Reichenhall court and the Berchtesgaden provostry.