The North Yorkshire Moors Railway (NYMR) witnessed a record number of visitors during last year, but managers have expressed growing concerns over the rocketing cost of petrol and diesel.
The railway, which runs between Pickering and Whitby, is heavily reliant on an army of volunteers to continue to operate.
But general manager Philip Benham admitted many of the 400 volunteers cannot afford to travel often long distances to help run the route.
The average cost of a litre of unleaded petrol now stands at 1.28, while a litre of diesel is 1.32.
Mr Benham said: "Like many tourist attractions in rural areas, the dramatic increases being seen in road fuel prices are a serious threat. For the NYMR, this is a 'double whammy', affecting not only visitors, but also the volunteers so vital to our operations.
"Often retired and on limited incomes, we are increasingly seeing cases where volunteers can no longer afford to make the journey to work on the railway. Some action by the Government to help stabilise fuel prices before the main tourist season would be most welcome."
A total of 355,000 passengers travelled on the railway's trains during 2010 – an all-time high and 5,000 more than the previous year, which itself was a record.
Research has shown that the NYMR is the world's most popular heritage steam railway, bringing in more than 30m a year to the local economy.
Spending power, however, was down last year, as visitors were reluctant to part with as much cash as in previous years. As a result, the railway's overall income of 5m for the year was 25,000 less than in 2009.
Meanwhile, motorists in remote areas may be given a discount on the cost of fuel under plans being considered by the Government.
Treasury Chief Secretary Danny Alexander said yesterday that the Government was taking steps to introduce a "discount scheme" for drivers in remote communities who depend heavily on their cars but are faced with higher fuel costs.
Prime Minister David Cameron has indicated that a fuel duty stabiliser was being examined, although Mr Alexander acknowledged there were difficulties with the plan.
The concept of a fuel stabiliser is to peg fuel duty to the price of oil. When the price of oil goes up the proportion of tax goes down, and vice versa, maintaining a steady price for consumers.
Jayne Dowle: Page 11.