The Cambrian Coastal line runs through mountainous countryside

The tourist trains, operated by rail company Arriva, are running on the Cambrian Coast line until 29 August.

It is hoped that the return of steam trains to the line will boost tourism in the area.

Hundreds of enthusiasts and locals turned out on Monday to watch the train travel along the Cambrian Coast line from Machynlleth to Porthmadog.

The trains are being provided by West Coast Railway which has operated the Jacobite steam train from Fort William in the West Highlands of Scotland for the past 10 years.

The trains start either at Aberystwyth, Machynlleth or Shrewsbury and run along the Cambrian Coast Line to Barmouth or Porthmadog, taking in some of Wales' mountain and coastal scenery.

'Extremely picturesque'

Managing director of Arriva Trains, Graeme Bunker, said the train service could be repeated in future years if they are a success.

He said: "The line is extremely picturesque and it is high time that a dedicated tourist service was introduced to do justice to its beauty.

"The tourist trains will provide a wonderful opportunity for both visitors to the area and local residents to enjoy the beautiful surroundings, in the unhurried comfort of vintage carriages, and to experience the glorious days of steam.

"If the trips are a success, we will be looking at repeating them in future years."

The last time steam train tours ran on the Cambrian Coastal line and over Barmouth Bridge was in 1991.

Wales Tourist Board chief executive, Jonathan Jones, said: "This is a popular destination for people visiting Wales and the romance and history of steam trains will provide a wonderful added attraction.

"I am sure that the scheduled runs will draw a large number of railway enthusiasts, many of whom might be visiting Wales for the first time."