Rail users across the north are being urged to pressure the government into making good on a mothballed pledge to upgrade the tracks between Inverness and Perth.
The Scottish Greens are urging the Scottish Government to carry out improvements to the Highland Main Line which were promised more than a decade ago.
Highland and Islands members of the party have launched a new campaign outlining the benefits of dualling the railway line.
They say it would improve capacity and reduce journey times to the north, along with the environmental benefits of cutting down on car use.
Currently two thirds of the 118-mile stretch from Inverness to Perth remains single track and has not been electrified.
Campaigners are now urging ministers to ”live up to their promises” made 13 years ago by former first minister Alex Salmond to upgrade the line.
Scottish Greens lead candidate Ariane Burgess said: “It just isn’t right that, in the 21st century, it’s often quicker to drive to the central belt from the Highlands rather than get the train.
“Meanwhile we’ve seen commitments to cut journey times by road and air, the transport modes which cause the most climate emissions.
“The need for improved rail connections is more urgent than ever.
“It’s time the Scottish Government lived up to its promise to Highlanders and improved the main rail line north, the first step in a fully integrated and greener public transport system.”
Supporters are now being encouraged to write to transport secretary Michael Matheson calling for the upgrades to be prioritised.
It is thought dualling the line could reduce the journey time by over half-an-hour and greatly increase capacity.
Highlands and Islands MSP John Finnie added: “It’s been 13 years since the Highlands were promised such a substantial upgrade to this vital link between the central belt and Inverness.
“Such a move would open up the Highlands to those who don’t have a car, lower transport emissions and could also drive freight off the A9.”
The campaign comes just seven months after experts recommended the creation of a task force to deliver “a more attractive, faster and sustainable service” which is able to compete with road travel on the A9.
A Transport Scotland spokeswoman said: “The recent £57 million Highland Mainline investment has already delivered performance and resilience improvements. This sits alongside the £330 million Aberdeen to Inverness project which has delivered new stations at Forres and Kintore, improving overall connectivity in the North-east and Highlands.
“Looking forward, the second Strategic Transport Projects Review (STPR2) currently underway will determine the Scottish Government’s future transport investment priorities and will include considering any rail infrastructure upgrades such as dualling the Highland Mainline.”