The Arade is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 located in the region of the Algarve, southern Portugal

Portugal

Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

. the river's course takes it through the municipalities

Municipalities of Portugal

In Portugal, municipality or concelho is the most stable subdivision of Portugal since the foundation of the country.Portugal has an entirely separate system of cities and towns. Cities and towns are located in municipalities, but often do not have the same boundaries, even if built-up is continuous...

 of Silves, Lagoa

Lagoa (Algarve)

Lagoa Municipality is a Portuguese municipality in Faro District, in the region known as the Algarve, with about 6,100 inhabitants.Its seat is the city of Lagoa....

 and Portimão

Portimão

Portimão is a Portuguese town located in the District of Faro in the Region of Algarve, the southern coast of Portugal. It was formerly known as Vila Nova de Portimão . In 1924, it was incorporated as a cidade and became known merely as Portimão. The town has 41,000 inhabitants and the Portimão...

. The source of the river lies to the southwest of the Serra do Caldeirão mountain ridge, in a valley called Barranco do Pé do Coelho. The river has a total length of 46.6 miles (75 km), with its source being 481 metres (1,578.1 ft) above sea level. The mouth of the river empties into the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 between the city of Portimão

Portimão

Portimão is a Portuguese town located in the District of Faro in the Region of Algarve, the southern coast of Portugal. It was formerly known as Vila Nova de Portimão . In 1924, it was incorporated as a cidade and became known merely as Portimão. The town has 41,000 inhabitants and the Portimão...

 and the freguesia

Freguesia

Freguesia is the Portuguese term for a secondary local administrative unit in Portugal and some of its former colonies, and a former secondary local administrative unit in Macau, roughly equivalent to an administrative parish. A freguesia is a subdivision of a concelho, the Portuguese synonym term...

 of Ferragudo

Ferragudo

Ferragudo is a Portuguese civil parish at the western border of the municipality of Lagoa Municipality, covering an area of 5.41 km² and encompassing a small population of 1867 inhabitants...

, in Lagoa Municipality.

From the time of the Moors up until the 19th century, the Arade was navigable up to as far as Silves (about 12 km), where an important port

Port

A port is a location on a coast or shore containing one or more harbors where ships can dock and transfer people or cargo to or from land....

 used to exist, especially for the cork

Cork (material)

Cork is an impermeable, buoyant material, a prime-subset of bark tissue that is harvested for commercial use primarily from Quercus suber , which is endemic to southwest Europe and northwest Africa...

trade. Nowadays only small boats can go that far.

Dams

Part of the reason for the present low water flow (and subsequent silting up) of the river has been the erection of two dams in the middle reaches of the river—the Barragem (Dam) de Arade and above it the Barragem do Funcho.