 The house and grounds are a popular visitor attraction |
A cheque for �10m has been donated to a trust bidding to run Elvaston Castle in Derbyshire. The money from a benefactor who wishes to remain anonymous could save the historic house from being leased off.
It is hoped the money will buy the site from its owners, Derbyshire County Council, which is selling the castle because it cannot afford the upkeep.
The cheque will be presented to the Elvaston Castle Estate Trust at 1000 BST on Friday.
Karen Sims-Neighbours, from the Estate Trust, said: "We want to make it so families coming here can have a fantastic day out.
"We find we have thousands upon thousands of people supporting us.
"We will keep fighting, because the money's there and we've got the skills and expertise on board.
"To lose this would be a crime and a great loss to Derbyshire."
Council officers say bidding for the historic house and grounds closed a year ago and they are already considering two other offers.
Little is known about the person or organisation which made the mystery donation.