Zeals House begins with a fanfare. As you pass through the impressive gates, which are topped by black Talbot hounds, you drive up the majestic S-shaped lime avenue. Nearing its end, the house comes suddenly into view, backed by trees and massed rhododendrons and with lawns running down to the lake. It forms a picture that takes you back in time, but how far requires further investigation.

The house, tucked away off the main road just beyond the pretty town of Mere in Wiltshire, is built of pale local stone. A bewildering array of gables and large stone mullion windows include signatures of the 14th, 17th, 18th and 19th centuries. It is as if three or four separate houses, with floors at different levels, are all packed together. Confusing but undeniably grand.

The challenge for the new owner is how to make sense of this fascinating labyrinth — where a ball of thread is needed to retrace your steps as you turn numerous corners and trot up and down short flights of steps. The present owner has colonised the service wing, where there is a kitchen and summer kitchen, breakfast room and dining room as well as a playroom and wine cellar in which to entertain.

For five centuries Zeals was the property of the Chafyn, and later Chafyn Grove, family who bought it in the 1400s and retained it until 1968. Before them, Matthew de Clevedon built, or rebuilt, a house here in 1372, and signs of this house are still to be found.

When you ascend to the attics you discover the spectacular oak roof of a late 14th-century first-floor hall surviving intact and unseen. It is a splendid affair that begs to be opened up. The crucial question is whether English Heritage would agree to it because the later room below contains a handsome early 18th-century Baroque marble fireplace. Yet, as you walk around, you can see that the house has a history of change, not always for the better, so another bout would be in the spirit of the place.

Part of the appeal of Zeals is the remarkably complete series of estate buildings. The circuit begins with a handsome red brick early Georgian orangery with characteristic large sash windows; each sash has 20 panes. Behind is the Georgian privy, large enough to have been a six-seater though apparently nothing remains.

Beyond, you emerge in a stable courtyard with matching blocks on either side. By the walled garden is a dovecote with 250 nesting boxes, and a granary raised on mushroom-shaped saddlestones to keep out the rats. But most intriguing of all is the walled, freshwater crayfish pond with a circular island in the centre. A perpetual feast awaits if you can make it operational. Then there is the pretty boathouse with a rustic arch and a horseshoe-shaped boat basin on the lake. And even the late Georgian icehouse survives, with a chamber set in a hillside.

Zeals House was requisitioned by the RAF during the last war and served as an officers’ mess. An adjoining airfield was used by Hurricanes and Spitfires. With extensive views over the Blackmoor Vale to the south, it is a perfect base for country pursuits. The house cries out for a large family with abundant energy for homemaking. In the right hands, its next transformation could be breathtaking.

FACT FILE

WHAT YOU GET: Grade I listed country house in 58 acres with 12 bedrooms, cottage, staff flat and two lodges. In all, 14,230 sq ft.

WHERE IT IS: Five miles from Gillingham, Dorset (London Waterloo is two hours away by train), 12 miles from Castle Cary (95 minutes to Paddington).

PRICE: £5 million. Contact the estate agent, Strutt & Parker, on 01722 328741.

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