Line 1 (Madrid Metro)

Line 1 of the Madrid Metro runs entirely underground from Pinar de Chamartín in the north to Valdecarros in the southeast, via Vodafone Sol. Today it has 33 stations (with 60-metre-long platforms) and spans 24 km (14.9 mi) from end to end. When it was initially constructed however, the line contained only 8 stops connecting Cuatro Caminos in the north to the city center at Puerta del Sol. Line 1 marks the start of the Madrid Metro with its inauguration on October 17th, 1919 and public service beginning 14 days later on 31 October. There have been various extensions to the line since it opened including the most recent northern extension to Pinar de Chamartin on 11 April 2007 and a southern extension on 16 May 2007 to Valdecarros.

Line 1 is the second busiest line on the Madrid Metro, behind Line 6, with more than 7.5 million monthly trips.

Line 1 of the Madrid Metro was opened on 17 October 1919 between Cuatro Caminos and Sol. It was extended from Sol to in 1921, Atocha to Puente de Vallecas in 1923, Cuatro Caminos to Tetuán in 1929, Tetuán to Plaza de Castilla in 1961 and Puente de Vallecas to Portazgo in 1962.

Between 1964 and 1966, station platforms were lengthened from 60 metres to 90 metres in order to allow 6-car train compositions, due to heavy increasing passenger flow. Chamberí station had to be closed because it didn't allow platform lengthening due to its sharp curve and its closeness to Iglesia station. The old Chamberí station however is still open to the public as part of the Madrid Metro's Platform 0 project and now functions primarily as a historic exhibition.

In recent years, the line has been extended both north and south. Firstly, in 1988 Atocha Renfe was added between the stations of Atocha and Menéndez Pelayo to serve the new long-distance rail station of Atocha. On 1 April 1994, it was extended from Portazgo to Miguel Hernández and on 4 March 1999 from Miguel Hernández to Congosto.

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Wikipedia