Archaeological findings in the Sahara Desert dating back before 7,500 BC show that ancient African communities organized one of the first calendars based on the 365 day cycle. At Nabta Playa in Egypt between 10,000-5,000 BC, when the Sahara had more vegetation, communities would converge seasonally and constructed a stone circle 13 feet in diameter used to track the summer solstice and rainy seasons. As the climate changed after 6,000 BC, these communities migrated to the Nile River Valley and continued developing calendars important for agriculture. The earliest Egyptian calendar was lunar but shifted to solar using the rising of Sirius to predict the Nile's flooding, establishing one of the first recorded calendars

1. The First Calendar Ife Madzimoyo African World History AYA Educational Institute

4. Nabta Playa Nabta Playa