River Tagus

The Tagus is the longest river in the Iberian Peninsula, stretching 1,007 km from its source in the Montes Universales near Teruel, Spain, to its mouth in the Atlantic Ocean in Lisbon, Portugal. It flows through four autonomous communities and six provinces in Spain and two districts in Portugal, passing through several major cities including Aranjuez, Toledo, Talavera de la Reina, Abrantes, Santarém, and Lisbon. The Tagus basin is the most populated in the Iberian Peninsula, with over 10 million inhabitants, and has a total area of 80,600 km2. The river's hydrological regime is irregular, with major floods occurring from January to April and lowest flows between July and October, and its course has been altered by the construction of engineering works for drinking water supply, irrigation, electricity production, and other purposes.learn more on wikipedia