Situated between the mouths of the River Tinto and River Odiel, Las Marismas de Odiel is a biosphere reserve that covers an area of 7 150ha around the towns of Huelva, Gibraleón, Aljaraque and Punta Umbría. Over 200 species of birds are indexed here, which makes for an astonishing avian spectacle, especially in February and March. The site can be visited by canoe or small boat, on an excursio that takes in both sections of the reserve: the Burro Reserve and Enmedio Island.