Egypt is located in northeast Africa and is divided into Upper and Lower Egypt. Lower Egypt was fertile land along the Nile River, which flooded annually and deposited rich silt. Upper Egypt was desert. Some notable developments in ancient Egypt include the building of step pyramids around 2667 BC, the Great Pyramid of Giza around 2560 BC, and the development of hieroglyphics around 3200 BC. Egypt was unified under King Menes around 3200 BC.