Ria de Alvor is the product of the confluence of four small rivers from the southern hillside of the Serra de Monchique that results in a wide and complex estuary system, protected from the ocean by two sandbanks with permanent dunes.
The beautiful protected area is situated between Alvor, Mexilhoeira Grande, Figueira and Odiáxere. Its 1400 hectares consists of a coastal lagoon (estuary), salt marshes, dunes, salt beds and the peninsulas of Abicada and Quinta da Rocha with their mixed habitats of bush, forest and agriculture.
It is the last not developed seaside area of the western Algarve and an important ornithological passage point of the Atlantic migratory corridor.

Ria de Alvor is included in the routes of migrant birds. More than seven million birds migrate seasonally between the north of Europe and the African continent across the Atlantic Ocean and the Mediterranean Sea. Many of those birds have Ria de Alvor as stopover point, using the existent habitats for food, as a refuge to rest and, eventually, for nesting.
Along the different seasons, there is a coming and going of different bird species that share the same space. Ria de Alvor welcomes more than 150 species of migratory birds annually.