old A32 trams (Flexity Swift) pic from wiki
new A35 trams (Urbos AXL) pic from wiki
Map from a few years ago. What's u/c or not is out of date, but these are the lines built, u/c and planned. pic from https://stockholmiana.wordpress.com/, originally from SL
Tvärbanan is a Light Rail Line that has some street running sections. It was somewhat controversial when it was built and some said almost no-one would use it and the parking it removed from one neighborhood would kill the local shops. Of course, that didn't happen. Very successful and has lifted that neighborhood to near inner-city level.
2000-01-08 Liljeholmen - Gullmarsplan (central part of the green section, the ends have transfers to the Red and Green subway lines, respectively)
2000-06-01 Liljeholmen - Alvik (western part of green section, connecting to the Green subway line on the other side of the Inner City from the one at Gullmarsplan as well as to the old suburban Nockebybanan tram line)
2002-08-14 Gullmarsplan - Sickla Udde (giving vastly better transit options to the Hammarby Sjöstad re-development area)
2006-01-09 new transfer to commuter rail at Årstaberg (existing Tvärbanan stop, new commuter rail station just for that transfer)
North expansion that is still in 2016 not thru-running with the old section(!):
2013-10-28 Alvik - Solna Centrum (transfer to the Blue subway and to commuter rail at Sundbyberg, to the other branch of the Blue line at SolnaC)
2014-08-18 Solna Centrum - Solna Station(transfer to the other northern branch of the commuter rail)
Currently under construction:
2017? Sickla Udde - Sickla Station (will connect to Saltsjöbanan, a sorta LRT-ish commuter rail-ish line)
Norra Ulvsunda - Helelund (transfers to both branches of the Blue line and ending with a transfer to commuter rail)
Alvik - Sickla Udde 11.5 km & 17 stops
Alvik - Solna Station 6.7 km & 8 stops
i.e. SolnaS - SicklaU 17.2 km & 25 stops
Extension to Sickla Station is under a km and 1 stop.
i.e. SolnaS - SicklaS 18 km & 26 stops.
Passenger numbers (per normal weekday):
2005: . 32 000
2007: . 44 000
2012: . 57 700
2014: . 62 000 for the main part, 13 000 for the northern part
2018: 110 000 for the whole line finally with thru-running and with the Sickla Station expansion.
The on-going f***-up that is the new signalling system was supposed to take about a year to get operational on the new northern extension. so was supposed to work after summer 2014. Still does not work. F*** GE and f*** the incompetence at SL that made the specs for the system. Hopefully it'll all work after summer 2017, when we might also see the Sickla Station extension go into service.