Two decades of neglect left a grand country estate once visited by monarchs with water running down the walls and a ceiling near to collapse.
But now, following emergency restoration by English Heritage, the people of Northamptonshire can get a glimpse of Apethorpe Hall's former glory before the historic estate is sold to a private buyer.
The conservation body is opening the hall, near Oundle, to the public for just eight days between now and the end of the month.
After that, it will be sold and only certain areas will be available for public viewing.
Visitors will be able to see the hall built for the Constable of Fotheringhay Castle, Sir Guy Wolston, in the late 15th century.
He was Esquire of the Body to Edward IV and both Sheriff and MP for Northamptonshire.
In 1551, the property was acquired by Sir Walter Mildmay, soon to become Chancellor of the Exchequer. He rebuilt the south range to provide a state apartment suite, where Elizabeth I was entertained in 1566.
Sir Francis Fane, who married Mildmay's granddaughter, remodelled the state rooms and added an oak-panelled long gallery in 1622, at the order of James I for his "more commodious entertainment and princely recreation there".
The King provided oaks for the purpose – at a discount – from nearby Rockingham Forest.
It was the seat of the Mildmays and Fanes, Earls of Westmorland, for more than 350 years.
The house was a favourite of Stuart monarchs.
There were at least 13 royal visits – more than to any other house in the county – between 1566 and 1636.
It is said that it was there that James met George Villiers, his "favourite", who was later to become the Duke of Buckingham.
The King's Chamber was built for James I and still retains its fine decorative plaster ceiling and an exceptionally ornate fireplace.
In 1904, the property was bought by Leonard Brassey, who carried out a major changes to the house, gardens and park with architect Sir Reginald Blomfield.
Lord Brassey sold the house and gardens in 1949, though retained much of the remaining estate.
The house then became an approved school, which closed in 1982.
When the school closed, Apethorpe went back into private hands.
But the Libyan man who bought it never occupied the estate and allowed it to fall into a serious state of decay.
Statutory action by the local council started in the mid-1990s and several Urgent Works Notices were served in 2000 to 2001.
Repairs were carried out when the owner took no action, but the building continued to deteriorate.
Then a Comprehensive Repairs Notice for more than 6 million of essential repairs was served by English Heritage and the Department for Culture, Media and Sport in 2001, followed by a Compulsory Purchase Order (CPO) in 2002.
However, the owner sold Apethorpe Hall to a property development company.
It produced proposals for subdivision into apartments, together with new houses in the grounds, but failed to address the repairs needed.
The compulsory purchase order was contested by developer and a public inquiry was held in 2004.
The inspector concluded that none of the developer's proposals would safeguard the hall and the order was confirmed.
English Heritage took over in September 2004 and began a 4 million programme of repairs.
The aim was to make the building water-tight and secure. The ceiling of the 110ft long gallery was sagging, due to water damage, and had to be supported by a crash deck during repairs.
English Heritage spent three years at the hall, re-tiling, repairing masonry, restoring ornate Jacobean plasterwork, preserving the fireplaces and oak panelling and demolishing post-war school buildings which had "disfigured" the site.
English Heritage believes selling the hall is the best long-term solution, but the new owner will have to continue the repair programme and maintain some public access.
The grade one listed estate is on the market for 5 million, but will take an estimated 8 million to 10 million more to make it habitable.