Wissigstock, Mountain summit in Urner Alps, Switzerland.

Wissigstock is a 2,887 m summit of the Urner Alps on the border between Obwalden and Uri, about five kilometres north-east of Engelberg. Three ridges meet at the top, which is the tripoint of Engelberg, Isenthal and Attinghausen. The Griessengletscher and the Schlossfirn lie on the flatter terrain to the west and north, while rock walls drop south-east toward the source of the Engelberger Aa.

The summit has marked the territorial border between Obwalden and Uri for centuries, serving as a natural reference point for the two cantons. Local mountaineers developed and documented climbing routes to the peak primarily during the twentieth century.

The summit is the tripoint of the municipalities of Engelberg, Isenthal and Attinghausen, and the three ridges running to the top are themselves municipal boundaries. Climbers approach from Engelberg, the Bannalp or the Isental via the Rot Grätli and the Engelberger Lücke, and the Rugghubelhütte lies about 3 km west of the summit on the ascent.

The summit is accessible via multiple routes that vary in difficulty and require mountain experience depending on the season. Summer offers the most favorable conditions while snow and ice during other months call for additional equipment.

The summit is the tripoint of the municipalities of Engelberg, Isenthal and Attinghausen, where three ridges that are also municipal boundaries meet. West and north of the peak the terrain is relatively flat and covered by two small glaciers, the Griessengletscher and the Schlossfirn.