Guadiana

The Guadiana is a major river of the Iberian Peninsula, running through Spain and Portugal. The name Guadiana is of Iberian-Arab origin, related to the word wadi, meaning river. The river rises in the western part of Spain and flows generally westward across the region of Extremadura, forming part of the international border with Portugal in its lower course before emptying into the Atlantic Ocean in the Gulf of Cádiz.

Its course includes the historic city of Mérida, situated on its banks. Mérida, known for its well-preserved Roman ruins, is a notable urban center along the Guadiana and reflects the long human use of the river valley. The Guadiana basin supports a variety of landscapes, from mountainous headwaters to agricultural plains.

A significant feature along the Guadiana is the Alqueva Dam in Portugal, which creates Europe’s largest artificial lake, the Alqueva Reservoir. Completed in the late 20th century, the dam supports irrigation for agriculture, generates hydroelectric power, and has become a focal point for tourism and water management in the region.

Hydrology of the Guadiana is characterized by seasonal variation, with higher flows in winter and spring and lower flows in summer. The river’s ecology and water-use practices are closely linked to the socioeconomic activities of Extremadura in Spain and the Alentejo region in Portugal, including agriculture, energy production, and cross-border cooperation on river management. The Guadiana remains an important natural and cultural feature of the Iberian landscape.