Footage by Dominic Carless
The new trams that will be used by passengers in the south Wales valleys and Cardiff next year are being test driven.
They will be able to run on both rail and tram lines and will operate on electrical lines and battery power.
Transport for Wales said that they can carry more than 250 passengers and on rail, run at around 60 miles per hour.
The overhead electric wires between Pontypridd and Cardiff were recently switched on. It promoted safety warnings for those who trespass.
The trams will connect people living in the Rhondda, Cynon, Taff and Merthyr valleys with Cardiff.
Lee Waters, Deputy Minister for Climate Change with responsibility for Transport, described it as "great news".
Alexia Course, Chief Commercial Officer at Transport for Wales said: “This is another major milestone for us at TfW. We’ve already introduced three new types of train to our network for passengers to use this year.
"We’re now pleased to be testing our light rail tram-trains that will operate a turn-up-and-go service on the South Wales Metro in the very near future.
“Wales has yet to experience light rail travel and these vehicles will provide faster, cleaner and more efficient travel."
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