— Line 11, coloured light green and currently known as Trinitat Nova - Can Cuiàs, is a recently built line in the Barcelona Metro network, operated by TMB, and part of the ATM fare-integrated transport network in the city. It is unusual in being actually an underground light rail line instead of a conventional metro line. It only has 5 stations as of 2007 but is going to be extended into areas of the metropolitan area of Barcelona nowadays only served by Renfe and FGC.
It is the latest addition to the main TMB network, having been opened in 2003. It serves the hilly and dense northern corner of Barcelona, from La Trinitat Nova - where it links with L4 - towards Can Cuiàs. It is currently undergoing construction so it is going to reach Universitat Autònoma de Barcelona and Ripollet. It's more accurately defined as a light rail-like addition to L4, still built under the standards of a regular metro line, as the addition of new stations was under consideration, and is already taking place. The colour assigned to this line by TMB is intended to represent a mixture of the official colours of L4 and L3, which join it at Trinitat Nova, its —at least temporarily— starting point. Additional metro lines projected to be built in following years will probably be quite similar to L11, and their colours have been designed using the same convention.
The rolling stock on Line 11 is the 500 series. Its composition is unique in the network, as there are just three two-car trains running on this line.