No photographs were taken, and no glossy brochures were printed. Only a handful of select buyers were invited for a tour of the hidden Regency splendour of Edgcote House and its 1,700 acres of park and farmland. And it sold within a fortnight.

The stately home, near Banbury, Oxfordshire, which was used as the backdrop to the 1995 television dramatisation of Pride and Prejudice starring Colin Firth, sold for close to £30m in June. It is believed to be the most expensive country house sale this year, as rival bids from two other seriously wealthy would-be owners pushed the price over the guide of £25m.

The successful purchaser is an unnamed charitable trust, about which no details are available, but which is said to want to invest in the model country house estate for posterity.

The transaction was, according to one of the agents involved in the sale, quickly and quietly handled. A discreet whisper at the right dinner party and the property had exchanged. The speed enabled the sale to proceed in secrecy.

Andrew Macpherson is a partner at CKD Kennedy Macpherson, the firm which made the private sale of Broomford Manor, Noel Edmonds’ Devon estate, earlier this year and which handled the Edgcote sale. He said: “It’s among the top places sold in the past 30 years. It’s a cracking estate, one of the most significant residential agricultural estates in the country.”

Edgcote was sold by Christopher Courage, 43, scion of the brewing dynasty, who was born there and had lived there all his life. Courage and his wife, Alexandra, and their two children are now renting a house in the area. Farm machinery and Courage’s 520-strong dairy herd were auctioned off in September in a sale that raised about £500,000. He declined to comment on the sale of the property which had belonged to his family since 1927.

Edgcote, which is Grade I-listed, was built between 1748 and 1754 for Richard Chauncy, a London merchant. Macpherson describes it as a “stunning, principally Georgian, house with double staircases sweeping up to the front door, which make it truly spectacular”.

According to somebody who visited Edgcote regularly when Courage lived there: “It is a highly traditional, totally unspoilt country estate. It’s a little raw in places, but lovely.”

A perfect home for entertaining, Edgcote House has a carved mahogany staircase that rises up from a grand entrance hall, with carved fireplace, and six finely proportioned reception rooms. The main drawing room, decorated with with Chinese wallpaper, was used by Alexandra as an artist’s studio.

The park was laid out in the 18th century and features a lake fed by the River Cherwell. As well as the six-bedroom main house, the estate has seven farmhouses, 15 cottages and five flats. The various estate properties will continue to be let and lived in by estate workers.

According to James Laing, a partner at Strutt & Parker, who advised the buyer: “The estate was bought as a whole and it will remain a whole.”

English Heritage estimates that only about 2% of listed buildings are Grade I. “Maintaining a Grade I-listed building is as long as a piece of gilded string,” says David Brock, a historic building inspector for English Heritage.

“The house may need a generational overhaul, as many do, in which case the bill will start at six figures.”

Included in the sale were two racing yards, an all-weather gallop, and a pheasant and partridge shoot. Milton Harris, who has his main yard at Edgcote, trains horses for former England and Surrey cricket captain Alec Stewart.

This may have been one of the attractions for David Allen, the leisure industry tycoon, who was rumoured to have been interested in buying Edgcote himself.

Knight Frank has sold 29 country houses in Britain with price tags of over £4m this year. Rupert Sweeting, head of the firm’s country houses department, claims that it has been involved with more than 80% of country house sales over £10m, though he will not put a figure on how many these amount to.

What he does say is that these figures, and the Edgcote sale, “only go to show just how strong the top end of the market is. Houses above £5m have risen by 10% this year,” he says.

“The rest of the market has been lucky to stay stationary, if not drop by 10%. It only goes to show that there is a lot of money about, and quality will always sell.”

It’s not just about buying a trophy home with a built-in sense of tradition. Buyers of substantial swathes of farmland can also make huge tax savings. One of the reasons that there was so much interest in the estate, says Sweeting, may have been the potential tax benefits of owning 1,700 acres of land. Under the Inland Revenue’s agricultural property relief (APR) rules, genuine working farms are usually exempt from inheritance tax, which means owners can substantially cut their heirs’ inheritance tax liability.

The speed with which Courage sold Edgcote — and the fact that he got more than the asking price — might prove galling news for another would-be seller of a similarly-priced nearby Oxfordshire property. Shaun Woodward, the former Tory MP for Witney, now Labour MP for St Helens South and under-secretary of state for Northern Ireland, put his Oxfordshire estate on the market for £25m in May.

Woodward and his wife, the supermarket heiress Camilla Sainsbury, have spent 11 years restoring the Grade II-listed Sarsden House, set in 450 acres of parkland, near the village of Churchill. Built in 1689, it has octagonal domes hall, private chapel and an orangery and the grounds include stables, clock tower, coach house, lake, walled garden and 11 farmhouses and cottages, but it has still not found a buyer.

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