Île-de-France tramway Line 1

Île-de-France tramway Line 1 (usually called simply T1) is part of the modern tram network of the Île-de-France region of France. Line T1 connects Noisy-le-Sec station and Asnières-sur-Seine with a suburban alignment running in parallel to the Northern city limits of Paris. The line has a length of 17 km (11 mi) and 36 stations. It opened in 1992 as the first modern tram line in the Paris region. The line was extended in December 2003 and November 2012. Daily ridership reaches 188,000 passengers (in 2015) making it the second busiest line of the tram network.

The line has been operated by the RATP Group since its opening, under the authority of Île-de-France Mobilités. Future operation of line will become subject to a competitive bidding process in November 2029.

A 1-stop extension to the west towards Quatre Routes opened to the public in mid-2019. A further extension to the west towards Colombes (which would allow for a transfer with Line T2) is currently at the planning stage. To the east a planned extension towards Val de Fontenay, which has been blocked for several years due to strong opposition from the municipality of Noisy-le-Sec, will finally be constructed in two stages with the first phase connecting Noisy-le-Sec station to Montreuil (Rue de Rosny) only.