Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Ecosystem and Relict Cultural Landscape of Lopé-Okanda' has mentioned 'Petroglyphs' in the following places:
Occurrence Sentence Text Source
The National Park includes the River Ogoouxc3xa9 valley, one of the principle migration routes for the diffusion of people and languages, including the Bantu, to Central and Southern Africa, in the Neolithic and Iron Age, as evidenced in extraordinary number of substantial settlements sites and an extensive collection of rock art petroglyphs.