The Kasbah of the Udayas is a kasbah (citadel) in Rabat, Morocco at the mouth of the Bou Regreg river opposite Salé, and adjacent to the old medina of Rabat. It is listed, along with other sites in Rabat, as a UNESCO World Heritage Site. It was built during the reign of the Almohads.

Rabat is the capital city of Morocco and the country's seventh largest city with an urban population of approximately 580,000 (2014) and a metropolitan population of over 1.2 million. It is also the capital city of the Rabat-Salé-Kénitra administrative region. Rabat is located on the Atlantic Ocean at the mouth of the river Bou Regreg, opposite Salé, the city's main commuter town.