to the south, and the Guadiana River to the east, along with its frontier border with the Andalusian municipality of Ayamonte (Spain). Due to its Atlantic frontage, the municipality has several kilometers of continuous sandy beaches. The topography of the municipality is diverse. Marshes are common, especially north of the city where a section of the salty wetlands became the Castro Marim and Vila Real de Santo António Marsh Natural Reserve (established in 1975, this was continental Portugal's first nature reserve). Woodlands cover the planar civil parishes of Vila Real de Santo António and Monte Gordo, while in Vila Nova de Cacela, barren lands and schist hills are more predominant. The easternmost part of the Ria Formosa system of lagoons is located in this civil parish. Ecoregions/Protected areas The establishment, in 1975, of the Castro Marim and Vila Real de Santo António Marsh Natural Reserve provided a refuge for several species of migratory and marine birds, namely mallards, flamingos, Kentish plovers, little terns, pied avocets, dunlins, stilts, white storks, and spoonbills, while at the same time protecting breeding grounds for local fish and crustaceans. Chameleons, oysters, and jellyfish (of the genus Rhopilema) are among the species that can be found in the region and its coastal waters, while carob trees, gum rockrose, brooms and almond trees mingle within the forests and brush within the interior. Climate Vila Real de Santo António has a Mediterranean climate (Köppen: Csa) with short, mild winters and hot, dry summers. November and December are the rainiest months, although on average, the municipality has around 300 sunny days a year. It has, in general, the hottest summer temperatures and coolest winters of the Algarvian coast. Human geography Vila Real de Santo António is one of the most densely populated municipalities of the Algarve, with a population density above the national average. Administratively, the municipality is divided into 3 civil parishes (freguesias): Vila Real de Santo António - this civil parish contains the city of Vila Real de Santo António which in turn is the seat of the municipality; Monte Gordo - the civil parish includes the seaside town and tourist resort of Monte Gordo, which is located less than three kilometers from the city of Vila Real de Santo António and separated by a large section of woodland. Vila Nova de Cacela - this civil parish is a (rare) exclave of Portugal; it is separated from