The nature park was created by Decree-Law 373/87, on 8 December 1987, and is considered one of the seven natural wonders of Portugal, with a beach that is around from the downtown. It includes the river and a lagoon system, interspersed with dunes, forming a small islands and peninsulas, that protect a large area of marshes, channels, and islets. The beaches in Faro are situated on the peninsula of Ancão and island of Culatra, along the corridor of the nature park. The park is a rich and complex aquatic ecosystem, consisting of barrier islands, marshes, and channels, comprising sandy shorelines that separate the waters of the Ria Formosa and Atlantic Ocean. The beaches of Faro and Barrinha/Barra de São Luís, are located on the Ancão peninsula, the beach of Barreta on the Ilha Deserta, and the beaches of Farol and Culatra are located on the Ilha Culatra. The barrier islands are separated by tidal flats and shallows, including (from west to east) the Barra do Ancão/Barra de São Luís, the Barra de Santa Maria/Barra do Farol, and the Barra da Culatra/Barra da Armona (in the municipality of Olhão).