Downton Abbey castle has its own tale to tell

As the taxi makes its way up the long winding drive, Highclere Castle appears out of the rain, all honey-coloured sandstone and regal turrets. It feels either as if one has gone back in time, or one is on a film set, which, in a way, we are: Highclere is familiar to millions of viewers as the “real” Downton Abbey.

Knowing my place, I call at the servants’ entrance, where a member of staff whisks me through below-stairs, past what is now the tea room, up a flight of stairs, through a green baize door and out into the main house. The “saloon” is Highclere’s central sitting room with comfortable armchairs gathered round a marble fireplace, and gold-embossed leather wall coverings brought from Spain in the 17th century. Remarkably, it manages to feel bright and almost homely: photographs of the Carnarvon family and their guests, including the current royals (the Queen is godmother to the Earl), adorn every surface.

Lady Carnarvon, the wife of the eighth Earl of Porchester and chatelaine of Highclere, breezes in, long skirt swishing, two young golden labradors trotting at her heels. Somehow, amid the demands of running a house with “between 200 and 300 rooms” (why be precise?), Fiona Carnarvon has found time to write two volumes about the history of the family, the second of which is out now, to coincide with the return of Downton Abbey for a fourth series.

We photograph her in the dining room while, under an immense portrait of Charles I on horseback by Van Dyck, the dogs growl and play-fight, their toes skittering on the polished floor. “I think I misjudged their bounciness,” she says. We’ve caught the castle in a brief moment of respite at the end of the summer season when the marquees are taken down and the stock counted in the gift shop. “Believe it or not we have a problem with storage space,” Lady Carnarvon says. With 200 to 300 rooms? “Yes, my girlfriends just laugh when I say that.”

Lady Carnarvon, 49, is elegant and charming, but the longer one spends in her company, the more one realises that a quiet powerhouse of efficiency is just beneath the surface. An accountant with Coopers & Lybrand, she married George (known as Geordie) in 1999, and they inherited the castle, on the Hampshire/Berkshire border, when his father died in 2001. They have a teenage son, Edward, who is at boarding school, and Geordie has two grown-up children, Saoirse and George, from his first marriage.

Highclere is rarely quiet. A steady programme of charity and corporate events and weddings continues throughout the year (Katie Price married Peter Andre here in 2005), and there is a farm and a stud to run. “Geordie and I do everything together, we have natural lines of what we do. He’s not really that bothered about cushions… he leaves that to me,” she says. “I tend to manage the detail of the properties and he tends to manage the detail of the farm. The gardens we divide: I do bulbs and he does shrubs, we both do trees and we both do annuals.”

That morning, she has done a building round. “I looked at extractor fans and quotes for the kitchens. There’s a leak in the guides’ room, there’s a new floor needed in the tea rooms. There’s a tumble dryer and washing machine which is supposed to be plumbed into one of the cottages today and a beech hedge which was being moved because they’re renovating some loos and I didn’t want them to kill it.” It sounds like being chatelaine of Highclere is less about being lady of the manor than about having a firm grasp of electricals and 19th century plumbing. “I am quite practical. The thing is, houses are practical. It’s a lovely light house, it works, the rooms are heaven, the views from the windows, it’s a lovely place to live. Our ancestors built a lot of houses very well.”

While there may not be as many staff as there once were, Highclere still needs a small army to keep it going, from the gardeners and handymen to the visitor guides and banqueting staff. Less than 100 years after they were built, many grand houses became barely viable: many were bulldozed, or turned into hotels or nursing homes. Lady Carnarvon says that by 1955, a great house was being demolished every five days. “I’m just amazed that Geordie and I are still here in some ways. There were so many near misses – we just squeaked through several times over.”

Like many aristocratic houses, Highclere now relies on paying visitors and corporate business to pay the bills. “Now it’s a business in a different way. When it was built, in 1842, it was a house which was lived in for utterly private purposes, now it’s not and I don’t have any problem with that. It’s a really good compromise. We’ve had to think, what is the role for a house, where is its relevance for people today, what are we going to do to make people appreciate it and value it, because without that they’re white elephants.”

Downton has helped, of course. While ITV doesn’t pay huge location fees, since the first series of the show went out in autumn 2010, coach parties visiting the house have risen six-fold. Lady Carnarvon points out that when she and Geordie agreed to the house being used for filming – partly because Downton creator Julian Fellowes and his wife Emma are old friends – they had no idea how successful it would become. Now it is watched by ten million viewers in Britain alone.

“We did it because we thought it would improve our marketing – which is obviously has.” Lady Carnarvon hoots with laughter. “Now we’re possibly the most famous stately home in England. My goodness, we hugely appreciate that. We’re very lucky.”

Downton films at Highclere for up to five months each year, and either Lady Carnarvon or castle manager John Gundill is present throughout, making sure the lighting rigs don’t scrape the Van Dyck and no one leaves their coffee mug behind a marble pillar. “Some of the rooms are quite delicate, and they arrive with masses of lamps and computers and banks of equipment.” A few lampshades might be replaced for the sake of period detail, but otherwise, Lord Grantham’s desk and Lady Grantham’s sitting room are exactly the same on screen as I’ve seen them today.

The main challenge is in the logistics – juggling filming schedules with the availability of actors such as Dame Maggie Smith, Hugh Bonneville and Michelle Dockery, the weather and Highclere’s existing commitments. “A bride is nonetheless very important and she wants to walk down the stairs on her special day without seeing Downton trucks outside the door.”

Lady Carnarvon admits she knows little about storylines for the new series and says she will be watching, though it’s odd to watch it at Highclere. “I much prefer watching it when I’m not here. My happiest times were watching it on a flight to States when I really enjoyed it because I was completely relaxed, and it wasn’t so up close and personal.”

We sit down with a pot of tea in the morning room, a bright space with sofas upholstered in soft florals and long windows looking on to the lawns where a couple of pheasants are strolling. The second series of Downton, in which the house became a hospital for soldiers returning from the trenches, first inspired Lady Carnarvon to write. Her first book, Lady Almina And The Real Downton Abbey, tells the story of the how the then chatelaine – like her Downton counterpart – opened the house as a hospital, though she nursed many of her patients herself. “She was amazing,” Lady Carnarvon says. “I thought, if she can do that, I can bloomin’ well write a book. And it is a lovely thing to do, having something of your own which you feel both supports your husband and his family home and is something that you’re passionate about.”

Her second book takes up the story of the house under Lady Catherine, wife of the sixth Earl, whose portrait hangs in the morning room. She wears a shimmering cocktail dress, her red-blonde hair in a characteristic 1920s wave. She and her husband (known as “Porchey”) inherited the castle after the sudden death of his father, the Egyptologist Lord Carnarvon, in 1922, shortly after the discovery of Tutankhamun’s tomb. Catherine was an American debutante who had lived in London with her widowed mother since she was 12.

Immediately, the couple had to battle to keep Highclere under a punitive burden of death duties, something they eventually accomplished through a mixture of economies and the strategic sales of jewellery and art. But the economies were relative. Lavish house parties continued at Highclere until after the Second World War (Evelyn Waugh, author of Brideshead Revisited and a guest of the family, described luxurious entertaining anywhere as “very Highclere”). Porchey was a generous host, a great storyteller and the life and soul of any party.

The “roaring Twenties” brought a new age of prosperity and permissiveness after the war, and the Carnarvons enjoyed the music and parties of the jazz age. But Lady Catherine, a sweet, caring woman, devoted to her husband and two young children, Henry and Penelope, was no party animal. “It was quite a brittle time, I found,” says Lady Carnarvon. “Quite wild and quite difficult. I sympathised with Catherine because I think some of the women had become instantly sophisticated. I re-read most of Evelyn Waugh’s novels – I always find them desperately sad, of lives half-lived, and I felt that was so much the spirit of that age, there were shafts of tremendous sadness or unfulfilled expectations.”

By the early 1930s, Porchey was spending more time in London, at his clubs and at parties, enjoying other female company, and Catherine was at Highclere, enveloped in sadness. “When I write, I’m looking for the tears or the laughter, and Porchey certainly provided me with the laughter [in his published memoir, No Regrets, and the much longer unpublished version]. I was just sitting there howling with laughter, thinking, ‘I don’t know how he dared write this down’. Then I found the tears, and I was sitting there feeling utterly miserable.”

A titled man, once he had made a suitable marriage and produced an heir, he was allowed to stray, as long as he strayed within his own class. “I’ve read some other diaries of men of the time, and that’s how it seemed to run. Some of the women were also more blatant and more open than they had been before the First World War. But it was very much always in certain circles. I never found anybody having an affair with the chauffeur or the gamekeeper. I’m sure they did, but I never saw any of that.”

Catherine and Porchey divorced in 1936, and Catherine, with a handsome settlement, her children and some of her favourite staff from Highclere, set up home in London. She married Geoffrey Grenfell in 1938, but he was killed when his ship went down during the Norwegian campaign of 1940. Porchey pursued his lover, Tanis Montagu, an heiress with ambitions to become a Hollywood screenwriter, to the United States, but she jilted him the night before their wedding, later eloping with a movie mogul. He married Austrian ballet dancer Tilly Losch, but they spent most of their married life apart. Both Catherine and Porchey lived into old age, much loved grandparents of the current Earl.

Lady Carnarvon enjoyed setting the stories of the family – and some of their servants – against the wider events of the time. Porchey, a friend of King Edward VIII and his brothers, was enlisted to help persuade the king not to abdicate to marry American divorcee Wallis Simpson. Porchey and Catherine’s son Henry fought in the Second World War, and Highclere opened its doors to evacuees from London.

She plans to write a “prequel about Charles Barry [the architect of Highclere who also designed the Houses of Parliament] arriving here and some cracking arguments about the size of the bloody bills from the builders”, but her next project will be a coffee table book about a year at Highclere, including recipes, anecdotes and practical advice: “How to black a grate, the best charades games.”

In the winter, she intends to explore the possibility of turning a suite of rooms in the tower into a museum about Barry. “Every so often I try and have a whizzo idea. We can all go up, take some tea, a kettle or a Thermos flask and have a go at deciding what the plan is. He was such an amazing architect, and if you have specialist groups it would make some sense.”

Does she ever have time to enjoy being chatelaine of Highclere? She and Geordie mostly live in a smaller house in the grounds, but they do still entertain guests here. “I think that brings the house alive, and it actually makes it much more interesting for people coming here, I hope; it has a warmth and a sense of heart and home.

“Some of the nicest times are when I’ve got a couple of friends round and we’re just having supper together. And recently, my husband had gone off somewhere, and I had breakfast here one morning on my own in the dining room, which was a very naughty treat. The staff thought it was a silly thing to do and they treated me to eggs Benedict – which was delicious.”

• Lady Catherine And The Real Downton Abbey, by the Countess of Carnarvon, is published by Hodder, priced £20. Series four of Downton Abbey starts tonight on STV, at 9pm