The chilly train service dubbed Scotland's polar express

A Scottish train service has been dubbed the "polar express" amid complaints of plunging temperatures.

Some commuters who travel between Oban and Glasgow say conditions in the carriages are so cold they take sleeping bags for the journey.

Now locals campaigning for better facilities are comparing it to the train bound for the North Pole in the 2004 Tom Hanks film The Polar Express.

ScotRail said it was looking into options to provide a better service.

The rail firm, which is wholly owned by the Scottish government, said the trains which operate on the route - the West Highland Line - are warmed by excess heat provided by the engine.

But in particularly cold spells they can take time to heat up, a spokesperson added.

On X, formerly known as Twitter, one train user, Martin Douglas, said the carriage he was travelling on was a "balmy" eight degrees.

He said: "The one next to this is 4.1C. The door is missing between this carriage and the one behind."

Mr Douglas also shared a photo of him inside a his wife's sleeping bag during the chilly journey which takes over three hours, adding that it was so cold the toilet had frozen over.

Other commuters have also reported taking hot water bottles onboard.

Ann McLachlan, from Taynuilt, took a photo of her husband, Terry Halcrow, during what she called a "dangerously cold" journey on 18 January.

It shows him wearing multiple layers and bent over in an attempt to heat up.

Another passenger can be seen in a jacket, and wearing a furry hat and gloves.

Ann told BBC Scotland News that on the day of the journey it was -10.4C outside. She said she would be surprised if the train carriage was above freezing.

"It never warmed up the whole way, it was absolutely freezing," she said.

"Terry is a Shetland islander, he's worked in the North Sea, he's used to the cold but he was absolutely frozen.

"Imagine instead of him that was a man or woman with a young child, or a frail elderly person.

"When we complained, ScotRail said they were sorry it hadn't been an enjoyable experience but this wasn't a quality issue, it's a health and safety issue."

Another passenger, Neil McInroy from Oban, said he often reaches for extra layers before travelling.

The 56-year-old added: "I've been on that train if I've been going away for the weekend, and I've had to put on all the contents of my bag, hats, jackets, jumpers, the lot.

"It's a three-hour journey, you're often on it for longer due to delays and if it's a cold carriage, that's horrible. It's pretty Baltic."

Mr McInroy said he made the journey three or four times a months but worried about the tourists who use the service.

"I got talking to a couple in their 70s and they were freezing, and on that particular journey there was no food trolley so they couldn't even get a warm cup of tea," he said.

"It wouldn't be a nice start to their holiday. Oban is a gateway to the Highlands and the islands, it's a really poor advert for Scotland," he added.

He said he felt locals were resigned to the fact the service was poor and have started calling it the "polar express".

The Class 156 trains which run between Glasgow and Oban are among 42 in ScotRail's fleet. Most were built in the late 1980s but some have since been refurbished.

David Lister, the rail firm's safety, engineering and sustainability director said they were looking into longer-term solutions for the heating problem.

"We know that the Scottish winter can make heating the first train of the day before departure very challenging," he added.

"Our staff are working tirelessly to ensure our trains are operating as reliably as possible.

"We continue to look into longer-term solutions and funding options which could improve on-board temperatures for our passengers."

But Ross Christie, who lives in Oban, says the plunging temperatures affect more than just the first train in the morning.

"Any time in the winter on that train, it's just uncomfortable, uncomfortable for almost three hours just sitting there and freezing," he said.

"It's the quality of the trains themselves, and how thin the metal is on the old-fashioned vehicles we have on the West Highland Line."

Transport Scotland said heating issues had been reported to ScotRail on the 08:21 Glasgow to Oban services on two occasions during random on-board testing.

The on-board heating was found to be below the ambient temperature on one occasion.