Twyfelfontein (Afrikaans: uncertain spring), officially known as ǀUi-ǁAis (Damara/Nama: jumping waterhole), is a site of ancient rock engravings in the Kunene Region of north-western Namibia. It consists of a spring in a valley flanked by the slopes of a sandstone table mountain that receives very little rainfall and has a wide range of diurnal temperatures.