Guadalquivir River, major watercourse of southern Spain. Rising in the mountains of Jaén province, it flows in a generally westward direction for 408 miles (657 km), emptying into the Atlantic Ocean at Sanlúcar de Barrameda, on the Gulf of Cádiz. It drains an area of 22,318 square miles (57,803 square km).
The Guadalquivir is among the longest rivers in Spain (along with the Ebro, the Tagus, and the Guadiana), and it has several distinctive characteristics. Its natural environment is one of the richest and most varied areas of plant and animal life in Europe. Its irrigative capacity, particularly in its wide and fertile plain, supports the rich agriculture of Andalusia, and engineering improvements have aided the industrialization of towns along its course.
The Guadalquivir rises almost 5,250 feet (1,600 metres) above sea level, in southern Jaén province, to the north of the Sierra Nevada fronting the Mediterranean Sea. It then flows northward for about 30 miles (48 km), running through a narrow valley. After emerging from the reservoir of El Tranco de Beas, it follows a westerly and southwesterly trend for the remainder of its course. Between the cities of Andújar and Montoro, the river cuts a widening plain. After passing the city of Córdoba, the Guadalquivir irrigates the fruitful regions of Posadas and Lora del Río before reaching Sevilla. From there the river meanders lazily across a hot coastal plain, traversing the swamps of Las Marismas, the largest in Spain, before reaching its mouth at the eastern end of the Gulf of Cádiz.
The drainage basin of the Guadalquivir encompasses one of the greatest floral resources of Europe, containing representatives of half of the continent’s species of plant life, together with nearly all those of the North African region. The surrounding mountains are covered largely by forests of pine and oak, but more than a third of the total surface is olive groves. In addition, cereals (wheat and barley) and viticulture support the regional agriculture.
Fauna is as varied as the plant life, with animals representing a great variety of European and North African species. In the mountains wild boar, goat, fallow deer, chamois, partridge, and many other animals are found, making the area one of the great European hunting regions. Fish, notably trout and barbels, are found throughout the Guadalquivir, its reservoirs, and its approximately 800 tributaries. Its main tributary, the Genil River, originates in the Sierra Nevada and flows into the Guadalquivir River at Palma del Río.