How the Olduvai Theory evolved For six years I lived and worked in Saudi Arabia. On vacation, I took a flight from Saudi Arabia to Nai-robi, Kenya on July 19, 1989. Following that, a tour bus took us southward to Tanzania and the Great Rift Valley, and then onward to the Olduvai Gorge. The Olduvai Museum is located close to the Gorge. Nearby is ...