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.

Displaying one of the largest concentrations of rock petroglyphs in Africa, UNESCO approved Twyfelfontein as Namibia's first World Heritage Site in 2007.

Twyfelfontein valley has been inhabited by Stone-age hunter-gatherers of the Wilton stone age culture group since approximately 6,000 years ago.

2,000 to 2,500 years ago the Khoikhoi, an ethnic group related to the San (Bushmen), occupied the valley, then known under its Damara/Nama name ǀUi-ǁAis (jumping waterhole).

[3] The area was uninhabited by Europeans until after World War II, when a severe drought caused white Afrikaans speaking farmers (Boers) to move in.

[11] The area is a transitional zone between semi desert, savanna, and shrubland and receives less than 150 mm (5.9 in) annual rainfall.

[3] Engravings of animals that certainly never occurred in this area, like a sea lion,[17] penguins,[16] and possibly flamingos[18] indicate that the hunter-gatherers might have ventured to the coast more than 100 km (62 mi) away.

[1] The findings do, however, support the shamanist origin of the engravings because food remains from the site proved to be bones of small antelope, rock dassie and even lizards rather than the large species depicted.

[2] In 2007, UNESCO approved Twyfelfontein as Namibia's first World Heritage Site[14][22] as one of the largest concentrations of rock petroglyphs in Africa.

The organisation recognised "a coherent, extensive and high quality record of ritual practices relating to hunter-gather communities [...] over at least two millennia"[11] (criterion iii), and "links between ritual and economic practices in the apparent sacred association of the land adjacent to an aquifer"[11] according to criterion V of the cultural selection criteria.

[23] To achieve having the site listed by UNESCO, the government of Namibia defined a buffer zone of 91.9 km2 (35.5 sq mi) to protect the visual setting.

[2] Although Twyfelfontein is regarded as "generally intact",[11] the Twyfelfontein Country Lodge within the "Zeremonienplatz" (Place of Ceremonies) rock engraving site in the buffer zone is of concern to UNESCO, who stated "This has severely compromised the integrity of the rock engravings in this area.

"[11] The hiking trail allowed visitors unsupervised access and is seen as running too close to many of the rock-art sites.