Plans are underway for a southern extension to Poble-Sec and Montjuïc, and eventually to El Prat airport.

However, the stations enjoy noticeably better lighting and do incorporate some more modern architectural principles, a symbol of its construction in the 1990s.

Plans for L2 to reach Montjuïc and Zona Franca in the southwest of Barcelona were first discussed as early as 1971, and another proposal for L2 to terminate near the Estadi Olímpic Lluís Companys was made in 1987.

Under the 2006 plan, L2 and L9 will share the same route from Terminal entre pistes (Aeroport T1) to Parc Logístic, at which point they will diverge.

L9 will then continue to the north toward Zona Universitària station, and L2 will travel to the east, entering the city centre.