The many pretty country houses of Jersey are either built of the island's delightful pink granite or faced in brightly painted stucco. Oaklands, dating from 1860, is a so-called cod house, built on the profits of the Atlantic cod trade, which Jersey merchants dominated.

For £6 million you can acquire the island's only fully walled estate, complete with a grand entrance drive that is wider than the main road. Within its 19 acres are avenues of tall, close-set limes like those surrounding many Normandy châteaux, a sunken garden, a lawn big enough to serve as a cricket ground and a kitchen garden with the most flourishing lemonry I have seen in the British Isles. “I took a crop of 1,800 lemons last year,” says Alan Miller, the vendor, with a laugh.

The south front has a pretty veranda supported by Greek columns with palm capitals. The long entrance front is more puzzling, with its four-stage tower that is inset with unusual mushroom-shaped windows. Miller bought the house two years ago from the estate of Dorothy Mackinnon, whose family had lived here in grand style since 1929 apart from the German occupation from 1940 to 1945, at the beginning of which the butler buried the silver in the garden.

Oaklands, right, is brightly painted and the lawns beautifully mown. “I've re-corded every sash,” Miller says proudly. Inside there's still a great deal of work to do. I would begin by introducing a dome over the imposing staircase to bring in much-needed light. The main rooms, as in most Jersey cod houses, are lofty and south-facing, and the main bedrooms have an equally sunny outlook.

Recently Belvedere House, on Guernsey, with stunning sea views but in a very basic state, sold for £5 million at auction. Oaklands almost rubs shoulders with Trinity Manor, the finest large estate on Jersey, and for those who want to put their own stamp on a house it has abundant potential. There are two date-stones from 1638 but these are incorporated from earlier, demolished houses on the site. One big question is whether you preserve the many intriguing marks of German occupation. The parquet floor of the billiard room was dented by hundreds of heavy shells that had to be turned every few days to keep their contents in prime condition. Fearful of a full-scale RAF raid, the German officers provided themselves with a bomb-proof shelter several feet deeper than the cellar, with a steel-plated ceiling.

The family silver was never found, as the butler died during the occupation, but the Rolls-Royce fared rather better. A haystack was built around it and the Germans never found it. After 1945, a grand car was urgently needed for the visit of the King and Queen, and the vehicle duly emerged. “How strange,” the Queen said with a smile, “this car smells of hay.”

Miller, who comes from Lancashire, owns Renaissance Living, a company that builds and runs retirement homes. At Oaklands he had planned a retirement village in the field to the north of the house, which would have acted as a club for the new residents. The scheme was rejected at a parish meeting and the property is back on the market as a single residence.

For an island little more than nine miles by five Jersey has an impressive series of grand manor houses - approximately one for each of the 12 parishes. But if it's a grand cod house you're after, with a decent amount of land, lofty ceilings and big windows, then Oaklands is in the top ten.

Details: Knight Frank, 020-7629 8171, and Thomson Estates, 01534 888855

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