Newgrange passage tomb
A tomb older than the pyramids, lit by the midwinter sunrise
Around 3100 BC Irish farmers raised a huge mound faced with white quartz over a stone passage and burial chamber. Once a year, at sunrise on the winter solstice, a beam enters through a roof-box above the entrance, runs down the passage and lights the chamber.
Wikipedia (Russian) · Wikipedia (English) · 31st century BC
Meanwhile around the world (±25 years)
Africa
- c. 3100 BC Unification of Egypt under Narmer — same year