Mértola is a Portuguese municipality in the district of Beja, region of Alentejo and sub-region of Baixo Alentejo, Portugal
 
Mértola is the sixth largest municipality in Portugal with an area of ​​1,292.87 km² and 6,205 inhabitants (2021 census). The municipality of Mértola is divided into 7 parishes: Alcaria Ruiva, Corte do Pinto, Espírito Santo, Mértola, Santana de Cambas, São João dos Caldeireiros, São Miguel do Pinheiro, São Pedro de Solis and São Sebastião dos Carros.

The municipality is limited to the north by the municipalities of Beja and Serpa, to the east by Spain, to the south by Alcoutim and to the west by Almodôvar and Castro Verde.

The village is located on an elevation on the right bank of the Guadiana river immediately upstream of the confluence of the Oeiras river.

The hydrology of the municipality of Mértola is marked by the Guadiana river and its tributaries (Oeiras, Chança and Vascão) cross the municipality for 35 km, making the tide reach Mértola, approximately 70 km from the mouth.

The municipality of Mértola in geological terms is characterized by two distinct zones: the Alentejo peneplain and the Guadiana valley.

Mértola has a warm and temperate climate, predominantly Mediterranean, with hot and dry summers as a result of the interior and little rainy winters.

Archaeological excavations that began in the late 1970s resulted in the discovery of remains dating back to the Neolithic era and information collected proves that the town of Mértola is much older than written sources testified.

In the invasion of the people of North Africa led by General Tárique in 711, Mértola gained a new dynamic, becoming the westernmost point of the Mediterranean.

At the end of the 19th century, with the discovery of the mining vein in S. Domingos, the municipality, especially the left bank of the Guadiana, experienced a new era of prosperity, characterized mainly by a marked demographic growth.

At the end of the 1950s, as mining exploitation diminished, the social and economic crisis set in for those who depended directly and indirectly on the mine.

In the 1980s, the town of Mértola began, through archeology, to better discover its past and transform this immense heritage into a factor of economic and cultural development.

The attractions are: Castle of Mértola, Main Church of Mértola (Church of Nossa Senhora da Anunciação), Ponte de Mértola (Torre do Rio), Archaeological Field of Mértola, Casa do Mineiro - Documentation Center, Mina de S. Domingos (parish of Corte do Pinto), Forja do Ferreiro Museum, Clock Tower, Museum of Islamic Art (Museu Municipal de Mértola), Azenhas do Guadiana, Cais de Mértola, Archaeological Museum - Museu de Mértola. Paleochristian Basilica, Mértola Civil Registry Office and Mértola Viewpoint.