The Oued Bou Khrareb (part of the Oued Fes), which divides the northwestern and southeastern shores of Fes el-Bali, is crossed by several historic bridges, some of which were first built before the unification of the two shores into a single city in the 11th century.[87] There were once at least six bridges, reportedly built by the Zenata emir Dunas ibn Hamama in the early 11th century, before the unification of the two cities by the Almoravids later in the same century.[88][3][87] Other scholarly sources, however, attribute at least some of the bridges to the Almoravid period (late 11th to early 12th centuries) when the two early cities of Fes were unified.[89] Many of them were destroyed in subsequent floods in the early 14th century, and only some of them were rebuilt by the Marinid Sultan Abu Sa'id at the time.[88]