coastal marshes along the Guadalquivir estuary in the comunidad autónoma (autonomous community) of Andalusia, southern Spain. The region extends for more than 1,100 square miles (3,000 square km), occupying part of the provinces of Sevilla, Huelva, and Cádiz. In Roman times Las Marismas was a large inland lake (Lacus Ligustinus). For centuries the region, noted for its birdlife, served as a hunting ground for the dukes of Medina-Sidonia. In 1963, at the suggestion of the World Wildlife Fund, it was established as a nature reserve, and in 1969 it became part of the Coto Doñana National Park. It is a winter home for ducks and geese and a sanctuary for hundreds of other bird species; about 20 species are year-round residents. The park is virtually the only remaining habitat of the southern European lynx; fallow and red deer, mongoose, wild boar, and wild cat are also found there. Parts of the marshes that have dried up are used to farm rice.