The importance of Doñana is enhanced by other wetlands in the province, such as the salt marshes of the Odiel river. These marshes are protected by virtue of their ecological values and are located a short distance from the city of Huelva.


The Natural Site of the Odiel Salt Marshes, a UNESCO Biosphere Reserve, is located on the banks of Huelva's tidal inlet, divided between the townships of Gibraleón, Aljaraque, Punta Umbría and Huelva. It is the second largest wetland in Huelva - second only in size, for its beauty and environmental value are incomparable. The protected area occupies 7,185 hectares of land and also includes the Natural Reserves of the El Burro Salt Marshes and En Medio Island. The Odiel Salt Marshes are the result of the interaction between the dynamics of the Odiel River current and the tides of the Atlantic Ocean, which has generated an intertidal ecosystem that attracts large numbers of broadbilled sandpipers and makes these marshes an important wintering site for various species of waterfowl. The fauna of the salt marshes includes the largest colony of spoonbill chicks on the continent, accounting for approximately one-third of the entire European population. They are also home to grey and purple herons, black storks, cranes and flamingos, as well as birds of prey often found in wetland environments such as the osprey and the marsh harrier.

This Natural Site contains the Calatilla Information Centre, which offers visitors various resources to help acquaint them with the location. In addition to the network of open-access hiking trails, which include several lookout points, and the information areas, guided tours organised by the company Onubaland are also available. These visits can be made on foot, in train or by boat, and they take visitors through different restricted areas in the company of an expert guide who provides information about the unique features of the setting and the different bird species. The routes that come close to the salt water areas grant such close-up views of birds - flamingos, for example - that visitors cannot help but feel privileged to have experienced this amazing corner of Huelva's natural landscape.