Ria Formosa is the largest wetland in Southern Portugal. The wetland is created by a complex of barrier islands, which form a chain of dunes that protect it from the sea. Apart from dunes and mudflats, the main habitats are reedbeds, saltpans, ponds, scrubland and Pine woods.
Ria Formosa is a congregation area for thousands of wintering waders, such as Oystercatchers, Avocets, Dunlins, and Little Stint, amongst others.