The spectacular botanical preservation and long occupation of Qasr Ibrim, Egypt make this site archaeobotanically matchless. 600 samples have been collected over 20 years covering a timespan of c. 1000 BC - AD 1800. The project has particularly focussed on the period AD 100-400 during which several new summer crops including sorghum, cotton, lablab and sesame first appear. These new crops are thought to be associated with the introduction of new irrigation technology, specifically a device known as the saqia, an ox-driven water wheel from which descends a conveyor belt to which pots are attached. It has never before been possible to examine this crucial change archaeologically and this project has allowed the investigation of when and how this great change happened. This has major implications for the history of agriculture in Africa and the Indian Ocean.