The Paris Metro, short for Métropolitain, is a rapid transit system serving the Paris metropolitan area in Francilian, the region of France's capital. A symbol of the city, it is known for its density within the capital's territorial limits, as well as its uniform architecture and historical entrances influenced by Art Nouveau. The system is 245.6 kilometres (152.6 mi) long, mostly underground, as well as its 321 stations of which 61 allow the riders to transfer between the sixteen lines, all numbered 1 to 14, with two extra branches, 3bis and 7bis, named such as they are former parts of Lines 3 and 7 respectively. Three of these lines are fully automated, and the additional four are also planned as such. Lines are identified on maps by an individual number and an associated specific colour, all part of an official palette, with the traveling direction indicated by the terminus, the last stop on each line. All trains travel from one end of the line to the other, serving every station along the way.