General
Population: Perhaps 27 million*
- Technology: Sumerians invent the sickle (2800 BC)
Africa
- Egypt: Old kingdom in Egypt covers 3rd and 4th dynasties (2800 BC)
Americas
- North America: "methuselah" the bristlecone pine tree sprouts in future California (2836 BC)
Europe
- Britain: The Beaker people haul and erect the bluestones for Stonehenge (2850 BC)
Possible start of Stonehenge (2800 BC)