Manzanares (river) Manzanares (river) The Manzanares () is a river in central Spain, which flows from the Sierra de Guadarrama, passes through Madrid, and eventually empties into the Jarama river, which in turn is a tributary to the Tagus. In its urban section, the Manzanares River as it appears today, with a section of water several meters deep, in some parts navigable by canoes, is the result and the product of the work of dozens of years of channeling and damming. The river Manzanares has its source near the Navacerrada mountain pass in the Guadarrama mountain range. The upper river basin is
Iowa River cities of Eldora, Marshalltown, Tama, and Marengo, and through the Amana Colonies in Iowa County. In Johnson County, it becomes impounded by the Coralville Dam in the Coralville Reservoir, which turns southward to the spillway. The river runs generally south and passes through Iowa City and the University of Iowa campus. A lowhead dam at Burlington Street in Iowa City is the last dam before the river's confluence with the Mississippi. South of Iowa City, it is joined in Washington County by the English River, and then in Louisa County it is joined by the Cedar River to flow into