The East African Pastoral neolithic culture builds East Africa's earliest and largest monumental cemetery at Lothagam North Pillar Site. (jan 1, 3000 BC – jan 1, 2300 BC)
Description:
https://en.wikipedia.org/wiki/Lothagam_North_Pillar_Sitehttps://en.wikipedia.org/wiki/Pastoral_Neolithic
Hildebrand, Elisabeth; et al. (2018). "A monumental cemetery built by eastern Africa's first herders near Lake Turkana, Kenya". PNAS. 115 (36): 8942–8947. doi:10.1073/pnas.1721975115. PMC 6130363.
https://pubmed.ncbi.nlm.nih.gov/30127016/
Added to timeline:
Date:
jan 1, 3000 BC
jan 1, 2300 BC
~ 700 years