The Tagus (Tajo in Spanish, Tejo in Portuguese) is 585 mi (940 km) long.
It is rising in the mountains E of Madrid, E Spain, and draining the
central part of the Iberian Peninsula. The Tagus flows northwest through
the mountains, past Teruel, then north across the Meseta of central
Spain, past Toledo, to form part of the Spanish-Portuguese border. Entering
Portugal, it flows southwest, past Santarém and into the Atlantic
Ocean at Lisbon. The estuary of the Tagus (12 mi/19 km long) is one
of Europe's finest harbors; one of the longest suspension bridges in
Europe, the Ponte 25 de Abril, spans the estuary. The Tagus is navigable
for c.80 mi (130 km) upstream. Its lower and upper courses pass through
deep gorges and are broken by waterfalls. Many dams and reservoirs have
been built on the Tagus and its tributaries to generate hydroelectric
power and provide water for irrigation. There have been efforts to reforest
the land surrounding the river. The chief tributaries of the Tagus are
the Alagón and Jarama rivers.
to the YWWF Tagus Wepage