The first of Greater Anglia’s new regional trains have entered service on lines between Norwich and the Suffolk and Norfolk coasts.
The Stadler Flirt bi-mode trains have been under test in the region since the end of last year, and was finally given its full safety certificate last month.
Now enough drivers have been qualified to take it out that the first unit is running on lines between Norwich, Lowestoft, and Great Yarmouth.
The trains are expected to enter service on other routes, including from Ipswich to Lowestoft, Cambridge, Peterborough and Felixstowe later this year. They will also be operating the trains from Sudbury to Marks Tey.
Jamie Burles, Greater Anglia managing director, said: "This is an important and significant day for us today - and one we have all been looking forward to. Our first new train has now entered passenger service and it's the start of a new era.
"We were committed to beginning our transformation in Summer 2019 and we've done just that.
"This is an incredibly exciting time for everyone involved with East Anglia's railways - customers, communities and all the team here at Greater Anglia."
A formal launch for the introduction of the new trains is due to take place later in the summer, as the phased entry into service for the new trains starts to pick up speed.
Greater Anglia is getting 38 regional bi-mode trains (24 x 4-carriage trains and 14 x 3-carriage trains) which switch between electricity and diesel power, from Stadler, which is based in Switzerland.
Thomas Ahlburg, group chief executive of Stadler, said: "The roll-out of the new trains into passenger service is a momentous occasion not just for our business, but for passengers and local communities alike.
A small number of services between to the coast will be operated by new trains - replacing the much-loved diesel locomotive-powered "short sets," followed by some services between Norwich and Cambridge.
The majority of the regional bi-mode trains should be in service by the end of 2019. Autumn 2019 will see the first new intercity train enter service and the first suburban train, built by Bombardier, is also due to enter service later this year.
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