Line 8 of the Madrid Metro opened between Mar de Cristal and Campo de las Naciones on 24 June 1998. An extension to Barajas via Madrid Airport was opened in 1999 and in 2002 an extension to Nuevos Ministerios and Colombia opened. Originally this line was a small-profile line, but in 2002 it became a large rolling stock line. The line uses 4-car versions of class 8000 trains. In 2007 an intermediate station called Pinar del Rey opened between Colombia and Mar de Cristal, as did an extension to the new Terminal 4 of Madrid Airport.
The line was temporarily closed for renovation from 26 January to 12 April 2017.
In a project to create new lines of the 70 envisaged, inter alia, the construction of a north-south line along the Castellana-Recoletos-Prado axis originating in Fuencarral and the south of station Atocha bifurcase, one part to the Puente de Vallecas and partly to Carabanchel. This stretch toward Carabanchel is the current line 11. From this project the construction of the section between Fuencarral and Nuevos Ministerios which opened on 9 June 1982 on the occasion of the celebration of the World Cup in Spain began, as the line gave service to Santiago Bernabeu Stadium.
Given the economic difficulties of Metro de Madrid in the 70s and 80s, the rest of the project from the original line 8 was discarded, and instead only tunnel that connected via line 8 to line 7 is enabled. This way, on Tuesday December 23, 1986, the extension of line 8 from Nuevos Ministerios and Americas Avenue was opened
The project developed between 1995 and 1998 to merge lines 8 10 by building a tunnel between Alonso Martínez and Nuevos Ministerios, left down the stretch Nuevos Ministerios - Avenida de America. Subsequently, on 10 December 1996 the tunnel was opened, after which the line 8 disappeared to lease its infrastructure to line 10. To make this possible, it was necessary to install the platforms projections because, since then, the stretch began to exploit narrow gauge trains.
Plans exist to extend Line 8 in the future beyond Nuevos Ministerios. Projected stops are:
Madrid Metro lines
Renfe suburban services
Renfe intercity services