The Vossloh Citylink is a series of tram-trains manufactured by Vossloh España at their Valencia factory since 2003. They are currently used in Spain and Germany, with the Class 399 variant expected to enter service on the Sheffield Supertram network in the United Kingdom from 2016 as the country's first tram-train.
In October 2011, Verkehrsbetriebe Karlsruhe ordered 25 Citylink tram-trains for operation on the Karlsruhe Stadtbahn network. The €75 million order also included options for a further 50 Citylinks. These Citylinks were known as the NET 2012, which stands for Niederflur Elektrotriebwagen 2012, German for "low-floor electric railcar".
The first Citylink was delivered to Karlsruhe in May 2014, around seven months behind schedule. Testing commenced on local railway lines on 19 June 2015. They are intended to replace high-floor trams on all lines except for Line 2, some of which are now up to 50 years old and are not wheelchair accessible.
Following their successful introduction, a further 25 NET 2012 vehicles were ordered in April 2015, scheduled for delivery from April 2016 onwards. An order for another 25 Citylinks was placed in March 2016.
Verkehrsverbund Mittelsachsen ordered eight NET 2012 tram-trains, with options for two more, for planned use on the Chemnitz Bahn network from 2015. In July 2015, a further four were ordered. Testing of the first tram-trains to be delivered commenced in September 2015. The Chemnitz Citylinks are fitted with a diesel generator to enable them to operate away from electrified routes, and they can also operate from 600V DC and 750V DC electrified lines. The centre section is also slightly higher, due to the differing platform heights in Chemnitz, allowing the doors in the centre section to be level with the higher platforms and the other doors to be level with the lower platforms.
The first Citylink entered service on the Chemnitz Bahn on 4 April 2016.
Nine Vossloh Citylink tram-trains were ordered by Ferrocarrils de la Generalitat Valenciana for use on the Alicante Tram network's lines 1 and 3. They have a maximum capacity of 303 passengers and a top speed of 100km/h, and are classified as the 4100 series on the Alicante Tram network.