Manzanares (river) protected as the "Parque Regional de la Cuenca Alta del Manzanares", a nature reserve which is recognised as a biosphere reserve by UNESCO. The Manzanares flows in a south-eastern direction from its source, and passes through the medieval town of Manzanares el Real where it is dammed to form the Santillana reservoir, one of the most important water supplies for the capital. The river then takes a southern direction and enters the Monte del Pardo, an ecologically valuable area on the edge of Madrid. The river is canalised where it passes through the built-up areas of the city. As at
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