Rare is the chance to buy a house built for a holder of the Victoria Cross. Lieutenant Lord Fincastle won his rescuing a wounded comrade surrounded by enemy swordsmen in the Khyber Pass in 1897. Ten years later the dashing Lancer succeeded his father, as 8thEarl of Dunmore, and commissioned one of the greatest houses on the St George's Hill estate that is today the retreat of Russian billionaires and Middle Eastern potentates.

The house was sold to the German Embassy in the 1930s and split into three in the 1940s. Now all three parts are for sale for a total of £15 million, offering a chance to recreate Thorn Hill as one of Surrey's grandest Edwardian mansions - and to join the modern elite of the super-wealthy who covet the exclusivity and privacy of a gated estate within easy range of Central London, Heathrow and Gatwick.

Driving into St George's Hill you enter a different world, of long avenues and winding drives, with 450 houses enclosed by rhododendron hedges. Guards man all the main entrances to the estate, which is similar in feel to the Wentworth estate. Numberplate recognition systems check every car that enters and leaves; this, combined with access cards at entry points for residents, adds to its all-round air of tight security.

Tom Culverwell, of Savills, says that there is still a market for superprime homes - those costing more than £10 million - in Surrey, particularly from international buyers. “Traditionally St George's Hill is six to eight months behind the rest of the market, so we have not seen a turn at the top yet. It is still strong, and there are still buyers with this sort of money who are out looking.

“Two or three years ago, buyers here were more Russian than Middle Eastern, but Russia has been hit by the credit crunch so buyers now are predominantly Middle Eastern.”

Like Wentworth, St George's Hill attracts the super-wealthy rather than the merely wealthy - CEOs rather than directors. Culverwell describes them as people with tens of millions to spend “rather than the odd £1million or £2million bonus”. He adds: “A lot of international buyers have a house in Central London, a house in St George's Hill, where they spend one or two months a year at best, and a main house overseas.”

Thorn Hill originally stood in 15 acres. Only 3 acres remain but it retains a glorious position approached up a winding drive with high hedges. The grand Neo-Elizabethan front springs into view with gables, clusters of tall chimneys and a splendid stone oriel window.

The Savills brochure includes the original plans of the architects Wood & Sarvis. It will take little more than the removal of internal partition walls to restore the Edwardian sense of spaciousness, which has a hint of the Prairie style of Frank Lloyd Wright in the way that the hall, drawing room and staircase flowed into one another. Long bands of mullioned windows look over the garden. These are repeated in the main bedrooms on the first floor, which have equally generous proportions - two measure 25ft and provide the sense of space demanded by today's super-rich buyers.

Thorn Hill stands on the crest of a hill looking over wooded Surrey countryside. To the west Windsor Castle rises on the horizon. Farther round you look across a valley to a hillside full of glorious autumn colour. The one niggle is a tall line of Leylandii screening the only neighbouring house that could be in view. Here a pretty formal garden of clipped box and yew has been laid out - the deer, it seems, were eating the roses.

The one surprise is to see a large crane at the bottom of the garden, where a substantial new house is being built farther down the hill. This is well out of sight, so a grand country house in spacious, secluded grounds is here for the making, as close to town as you could hope to be.

Fast facts

What you get: One of the first and largest houses in St George's Hill, Surrey, in secluded grounds with glorious views, split into three houses but available for re-creation as one grand house with a dozen bedrooms. In all, 16,776 sq ft and 3 acres.

Where is it: Two miles from Weybridge, Surrey, from where trains to London Waterloo take 35 minutes. Heathrow is 18 miles, Gatwick 30.

Price: £15 million via Savills, 01932 838000, www.savills.co.uk

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