This article examines the genesis of the city of Aġmāt Ūrīka (Morocco), a Medieval regional capital about 30 km south of Marrakech (founded later by the Almoravids), as well as the evolution of irrigation and the city’s supply network. Although this network has evolved over the centuries, it is still observable today. A field survey, the analysis of vertical aerial photographs and the observation of the archaeological remains of the city itself allowed the establishment of a relative chronology. This research leads to the conclusion that the urban foundation of Aġmāt and the establishment of the irrigated network were indeed contemporary, while the historic sources suggest dating this joint process to the 9th century.