Huacshash, Mountain summit in the Andes, Lima Region, Peru.

Huacshash is a 5,644-metre summit in the western Huayhuash range of the Andes, in Cajatambo Province, Lima Region. Its upper part is snow and ice over a pointed, roughly pyramidal peak, with dark grey and black rock faces and gullies descending below the snowline toward brown and tan rolling terrain. It lies south of the Huayllapa River and north of the Pumarinri River.

Huacshash lies in the western part of the Huayhuash range, in the Cajatambo District of Cajatambo Province, Lima Region. The range's name is shared with the villages of Huayllapa and Auquimarca to its northwest, and the mountain sits between the Huayllapa River to the north and the Pumarinri River to the south.

The name Huacshash comes from Quechua language, where 'waqsa' means eye tooth and reflects how indigenous Andean communities named their surroundings. This linguistic connection shows how the local culture is embedded in the geography of the region.

Climbers need proper acclimatization and technical equipment to reach the summit, with access routes available through the valleys near Huayllapa and Auquimarca villages. Visitors should prepare for high altitude conditions and the physically demanding nature of the climb.

Huacshash reaches about 5,644 metres (18,517 ft), the highest figure given for the mountain in the sources. It lies in the western part of the Huayhuash range, south of the Huayllapa River and north of the Pumarinri River, southeast of the villages of Huayllapa and Auquimarca. The name may come from local Quechua waqsa, meaning eye tooth.