Morwellham Quay's trustees say millions invested in the site will be lost
A Devon tourist attraction is to go into liquidation at the end of the week, unless further funds can be found to keep it open.
The mining village at Morwellham Quay near Tavistock has lost its funding from the county council.
Trustees said they were continuing negotiations with other possible sources of money.
But unless more money was forthcoming by Saturday, the attraction would be put into liquidation, they said.
The replica Victorian mining village attracted more than 150,000 visitors each year during the 1970s, but that number has since dropped to 50,000 annually.
The county council, which provided an advance of £1.2m to keep it open, said it was pulling the plug because it had not received a business plan as requested.
The trust rejects the claim, adding that £5m of public money invested in the site will be lost.
The bulk of the money has come from the Heritage Lottery Fund, the Government Office for the South West and the Regional Development Agency.
Chairman Michael Stone told BBC News: "There's an extremely serious chance that quite a lot of it will have to be repaid."
He said that there would be a "great deal of sadness and incomprehension" if the site went into liquidation.
He said: "The nearer I get to Saturday the less optimistic I become, but I still cannot believe that we will not find some sort of support."
The attraction would still be run on a limited basis through the winter to honour commitments to school parties who are booked to visit the site.
In 2006 the former mining area around Morwellham was designated a World Heritage Site by Unesco and £2m was spent improving the site.
A major Devon tourist attraction could be forced to fold in a looming cash crisis