El Salvador has over 300 rivers, the most important of which is the Rio Lempa. Originating in Guatemala, the Rio Lempa cuts across the northern range of mountains, flows along much of the central plateau, and cuts through the southern volcanic range to empty into the Pacific. It is El Salvador's only navigable river. It and its tributaries drain about half of the country's area. Other rivers are generally short and drain the Pacific lowlands or flow from the central plateau through gaps in the southern mountain range to the Pacific. These include the Goascorán, Jiboa, Torola, Paz and the Río Grande de San Miguel.