The 2006 article quoted in this video can be found here.
"The Tsodilo Hills are a UNESCO World Heritage Site (WHS), consisting of rock art, rock shelters, depressions, and caves in southern Africa. It gained its WHS listing in 2001 because of its unique religious and spiritual significance to local peoples, as well as its unique record of human settlement over many millennia. UNESCO estimates there are over 4500 rock paintings at the site." (Wikipedia)
Some of the petroglyphs can be seen starting at app. 1:27.
"People have used the Tsodilo Hills for painting and ritual for thousands of years. UNESCO estimates that the hills contain 500 individual sites representing thousands of years of human habitation. The hills' rock art has been linked to the local hunter gatherers. It is believed that ancestors of the San created some of the paintings at Tsodilo, and were also the ones to inhabit the caves and rock shelters. There is evidence that Bantu peoples were responsible for some of the artworks at the hills. Some of the paintings have been dated to be as early as 24,000 years before present."
Related: A 2012 hiker's travel report for the Tsodilo Hills.