Taxpayers are having to foot the bill for the extra costs in fixing the structural issues with the Scottish Government agency-owned Cairngorms mountain railway to the tune of £9m.
The 1.3 mile funicular will not now reopen for the start of this winter season and is due to relaunch early next year - having seen costs spiral from an original price of £14.8m.
Calls have previously been made for a public inquiry into the management of the Cairngorm funicular, which it was hoped would re-open in late 2022.
It has meant the ski centre above Aviemore in the Scottish Highlands will remain without its main lift for a fourth successive ski season.
The Cairngorms are a major Scottish tourism attraction and centre for recreation with downhill hillwalking and rock climbing a major draw for the 1.92m who visit the national park every year from around the world.
But the crucial funicular, which was opened in 2001 and connects a base station with a restaurant and a ski area 1,097m (3,599ft) up Cairn Gorm mountain near Aviemore, has been closed since September, 2018 due to structural issues.
It has now been confirmed that the cost of the urgent repairs have risen by 56% from £16.16m to £25m.
The faults were discovered after the actual costs of building the funicular spiralled from £14.8m to £26.75m.
According to the Cairngorm National Park Authority strengthening works to the railway viaduct involves reinforcing props and concrete bases beside 63 out of 94 piers.
Past concerns have been raised from within the funicular's owner, the Scottish Government's Highlands and Islands Enterprise agency about how it will be paid for.
HIE said it has "reallocated uncommitted funds" from a wider Cairngorm masterplan capital investment package to meet the additional costs. The Scottish Government also allocated £7m additional funding in June 2022.
HIE says it will continue to pursue legal action against the funicular’s original designer and construction contractor in the Court of Session, in a bid to recoup public funding.
The Herald revealed the early stages of the £14.5m claim last year against the now owners of Morrison Construction, Galliford Try Infrastructure Limited and Inverness-based AF Cruden Associates Limited, the civil and structural engineers for the scheme which had been taken over by Glasgow-based Arch Henderson.
The decisions over the contracts for the funicular were hit with allegations of cronyism and financial mismanagement that led to an investigation after chief executive of HIE, Iain Robertson, announced in 2000 that he would be leaving to become director for corporate development for Morrison plc, an Edinburgh-based construction company founded and once chaired by one of Scotland's wealthiest men Sir Fraser Morrison.
In five years HIE had awarded a number of Morrison contracts including that for the building of the controversial railway up Cairngorm which they eventually received more than £10m for.
Morrisons were awarded the funicular contract in 1999, a year after Sir Fraser left HIE.
Audit Scotland said there was no conflict of interest in either case.
Scottish Conservatives' Highlands and Islands MP Edward Mountain MSP said he was not surprised by the rise in costs.
"One questions who has been managing this asset for the country.
“Would we have been better installing a different form of lift to get the capacity we need at a lower cost? Also, how much will the previous operator contribute to the final repair bill?
“If the funicular is ready for winter 2023 then this would be a huge boost for a local tourism industry.
“While I am pleased, following my calls earlier this year, that the Scottish Government committed a further £7m to the repairs, I am however concerned that HIE have had to reallocate funding from the Cairngorm masterplan investment package.
“Many will be left wondering what knock-on impact that will now have on the masterplan and I will be seeking further clarity on this matter.”
The Herald previously emerged that having already pumped more than £10m in works to fix it, ministers and officials were considering scrapping the project altogether.
A dossier of internal Scottish Government documents seen by the Herald showed that business minister Ivan McKee ended up sanctioning continuing with the project as the "least worst option" while warning additional finance could not be guaranteed.
The enterprise agency said that the project costs rise is due to the impacts of Covid, Brexit and blizzards in spring hampering repairs.
Trains are running on the mountain railway for the first time in four years - though under test conditions for now.
Testing on the funicular is expected to continue into December and safety certificates will be needed from the UK Department for Transport before it can be opened to visitors.
Hector MacAulay, managing director of Balfour Beatty’s UK Construction business in Scotland said: “As the project nears completion, we are excited to see the benefits the Cairngorm funicular railway will provide, enabling local residents and tourists alike to access the unique mountain environment all year round.”
Contractors will continue to work on the mountain removing final materials and demobilising until the end of the year.
Environmental restoration works, including replanting and re-seeding, will proceed during 2023 and beyond.