Please answer the following question: Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Guadiaro (river) - The Guadiaro is a river in the Spanish provinces of Cadiz and Malaga in the autonomous community of Andalusia Spain. It flows southward from the Sierra Bermeja through the Sierra de Grazalema and discharges into the Mediterranean at Sotogrande. The river is notable for having some of the only marshland on the Costa del Sol. This marsh is protected by a 27 hectares (67 acres) nature preserve.
A:
Natural Place