UK: Non-passenger-carrying tests of the Class 399 tram-train vehicles have started on the Supertram network in Sheffield. Driver training is due to begin shortly, with passenger services on the existing tram network now expected to begin in mid-2017. Testing on the national rail network is currently expected to start next year, with tram-train services between Sheffield and Rotherham now planned for 2018.

Stadler Rail Valencia has delivered seven Citylink tram-trains since late 2015, under a contract awarded in 2013. The eventual service pattern would see three services per hour run from Parkgate Retail Park in Rotherham to Rotherham Central station, before joining the existing Supertram network via a new connection at Meadowhall South and then running to Sheffield city centre.

The tram-train pilot is being led by South Yorkshire Passenger Transport Executive in partnership with the Department for Transport, Network Rail, tram operator Stagecoach Supertram and franchised train operator Arriva Rail North. As well as new rolling stock, it includes infrastructure work to enable the proposed service.