The saying goes that “a change is as good as a rest”, and Felicity Loudon believes that a spell away from home, no matter how brief, can be invigorating. So when husband Johnny is away on business or she just fancies a brief adventure, Loudon and her basset hound Wee Wee head off to her showman’s caravan in the grounds of the family house and farm on the outskirts of Oxford. “It’s only a short walk from the house but it feels a world away,” she says.

The caravan is a contemporary version of a Victorian “Reading Wagon”, a traditional circus artiste’s travelling home. The compact 15ft-long and 7ft-wide cabin is raised from the ground on a double-axled steel trailer-base. The exterior of the cabin is clad in black wood panelling and topped with a corrugated tin roof.

“The fact that it is mobile means that I can put it in different locations during the year,” explains Loudon. “In the spring it’s nice to be in the orchard and in the summer by the lake or a cornfield, but during the autumn it needs to be stationed close to the house so that the light and heating can be plugged in to the mains electricity.”

Inside the black utilitarian exterior Loudon has customised her caravan to be a luxurious retreat. The walls of the sleeping area are tented in black and white ticking, and around the raised box-bed the small windows are framed with blinds and curtains in the same distinctive fabric, so that when they are drawn the interior is cosily enveloping. The fabric also provides insulation at cooler times of the year.

There are windows on three sides, but not on the long back wall because traditionally this was the side that faced outwards as the vans were circled around and camp was made. When the wagon is on the move, the stout steps that lock on outside the door can be stowed away, as in the original design, in a deep box built on to the wagon’s steel frame.

Matching floor-length curtains can be closed to separate the sleeping space from the compact kitchen with its small enamel stove and ceramic sink. The kitchen units and shelves are built-in, but other pieces of furniture are designed either for sailing boats or in the style of the fold-away and packable furniture used in field tents during war campaigns. And when the wagon rolls, the candlesticks and coffee pots must all be neatly and carefully put away in baskets and cupboards so that they aren’t damaged in transit.

Although the bolt hole is small it does not compromise on luxury. The bed is made up with crisp monogrammed linen sheets and pillowcases, and covered with a black, cable-knit cashmere blanket, part of a collection of cashmere clothes and accessories she has designed to be launched this autumn.

Candlelight adds to the feeling of being in another place and even another time, and in the evening if it is balmy or a visitor comes by for supper, Loudon likes to dine outside. To accommodate this she has a pair of black wrought-iron chairs and a table in a swan design by Cecil Beaton.

The wagon has often been used as an overflow guest room for family and friends. And it has proved to be such a hit with those who have sampled its delights first-hand that Loudon has started a business making more wagons to order. One has been kitted out as a gambling room for a man whose wife refuses to let him bet or smoke cigars in their home; his customised casino with bar is soon to be towed into place at the bottom of his garden. A writer enquired about one as a writer’s retreat and another was bought, fully fitted out to the last candlestick and cushion, as a Christmas present.

“The space is quite adaptable,” says Loudon. A generator and small water tank can be fitted under the cabin to make it independent of mains water and power, and the decoration of the interior can be customised to any style.” Prices are from £25,000.

Marie Antoinette may have had her “home from home” at Le Petit Trianon, but Felicity Loudon has hers in a Victorian wagon, and is thankfully in no danger of losing her head over it.

The Private House (01367 870400; www.theprivatehouse.com)

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