The first passenger train service between the Ebbw valley and Cardiff for 46 years has started, after a two-month delay because of engineering issues.
The first train left Ebbw Vale at 0640 GMT, with transport minister Ieuan Wyn Jones on board, and arrived early.
A service in the opposite direction departed from Cardiff at 0635 GMT.
A £30m refit of 18 miles of track was needed to make it suitable for passenger trains. Previously, only freight services used the line.
Trains will run hourly in each direction until 2240 GMT Monday to Saturday from Ebbw Vale and call at Newbridge, Risca and Pontymister, and Rogerstone en route to Cardiff.
There will be seven services in each direction on Sundays.
Two more stations along the line at Llanhilleth and Cross Keys are being built.
Blaenau Gwent council leader Hedley McCarthy described the service as "the catalyst for the economic regeneration of the area".
He said: "It brings the jobs from the vibrant economy of Cardiff much closer to the people of Blaenau Gwent and at the same time it brings affordable housing nearer to young professionals who may not be able to afford Cardiff.
"I'm hoping it will mean an increase in our population."
He also hopes the train link will give tourism a boost. "At Parkway [where the station is], we have just had a new hotel open so all the pieces are fitting into place.
"A rail link from Abertillery to Newport will be the next thing we will be pressing for," Mr McCarthy added.
A ceremonial opening in December had to be cancelled while a number of infrastructure works were carried out.
Kevin Hutt, from Ebbw Vale, said he and his wife primarily travelled to Cardiff to shop but that meant paying for petrol and parking.
"It takes about an hour-and-a-half to get from Ebbw Vale to Cardiff on the bus. That's horrendous," he told BBC Wales' news website.
"You get on in Ebbw Vale and an hour later, you're still in Merthyr.
"At the moment the better option we had was by car. Rail would be a lot quicker and cheaper.
"I think it's quite exciting for the town. It makes you feel less cut off from the city."
'Worth the wait'
Deputy First Minister Mr Jones, who is also responsible for economic development as well as transport, said he believed the line would refelct the growth in train passengers.
He said: "I believe that this new service will confirm that trend and will do so in a way that will benefit these communities."
On the subject of the delay in opening the line he said: "It was only 46 days late and when you've waited 46 years for the new service to start, I think it was well worth the wait."