Knebworth House: The stately home bringing Hollywood to Hertfordshire

Michael Keaton drove up to the Courtyard as Bruce Wayne in Batman (1989)

The "fantasy façade" of Knebworth House hides a red brick house that dates back to Tudor times, says Henry Lytton-Cobbold.

It is something of irony, says the 3rd Baron Cobbold, whose family has lived at Knebworth House since 1490, that the building itself is "almost like a film set".

With its Gothic exterior and Victorian decorative additions from the 1800s, Knebworth "expresses lots of different periods" with its Jacobean hall, Edwardian drawing room, Victorian library and a Regency bedroom.

Such an eclectic historical mix, he says, has made it very popular with film studios.

Directors including Tim Burton and Stanley Kubrick have been inspired by its appearance and actors such as Dame Judi Dench, Colin Firth, Helena Bonham Carter and Guy Pearce have walked along its halls.

Now, with construction on a £700m film and TV studios in Waltham Cross due to begin and Sky building a huge new facility at nearby Elstree, Lord Cobbold hopes his home will be "their preferred location".

Claire Foy and Matt Smith are just one Queen and Duke of Edinburgh who have filmed at Knebworth for The Crown - seen here in the Banqueting Hall - the house has been Balmoral a number of times but only inside as the real thing has "a very distinctive outside".

Knebworth has "played" Balmoral about five times, but Lord Cobbold said it was important to not become well-known as one place.

"We've only ever played Balmoral from the inside," he said. "We want to continue to be used for all different sorts of things and not to be too attached to any one show."

Actors can also be accommodated, such as when Colin Firth and Helena Bonham Carter had to stay during the winter filming of The King's Speech when the weather was particularly bad.

Unfortunately, Firth got lost when heading for breakfast and was escorted out of the building into the snow by Knebworth's head of maintenance who did not realise who the actor was.

Firth had to climb over a wall to reach the film crew area as the courtyard gates were locked and nearly missed his make up call.

Helena Bonham Carter and Colin Firth both stayed at Knebworth while filming The King's Speech (2010) - see here in the Banqueting Hall in

But Lord Cobbold, who has worked in film, said: "We will always do our best to make things work... we try to be as accommodating as possible because we understand the way it works," he said, "but sometimes things are not possible".

For example, haze, which is used to create a diffuse filming environment, cannot be used in all rooms as it causes damage. And when the producers of the Netflix series You asked if they could take a window out of the Falkland Room, the answer was a polite "no".

"The last time a window came out was for Charles Dickens in the 1860s so he could get an instrument in," said Lord Cobbold. "But we couldn't do it for Netflix."

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Netflix series You asked if they could take a window out of the Falkland Room

And when filming ends, house staff rush to check their treasures do not get mixed up with film props.

"It's always the most nerve-wracking bit," Lord Cobbold said, "everything is being piled into the back of a truck outside and you are nervously wondering whether any of our bits and pieces are in there as well.

"But there have been occasions where the props are more valuable than the things that we've got here, so often they're more worried about leaving things behind."

Filming highlights

• Scenes in the banqueting hall include the dining sequence in Batman and The Ghillies Ball at Balmoral in The Crown

• The Courtyard features in 52 seconds of Transformers: The Last Knight and Batman drove up to the gates in 1989 where Kermit had delivered pizza in 1981's Great Muppet Caper

• The grounds were used in Paddington 2 and The Flash, which will be released in June

• The bed in the Queen Elizabeth bedroom has been slept in by Claire Foy, Imelda Staunton and Olivia Colman in The Crown, and Dame Judi Dench in Victoria and Abdul

• The picture gallery has been Colin Firth's study in the Secret Garden and Helena Bonham Carter's bedroom when she was Princess Margaret in The Crown

• Music videos filmed include Tears For Fears' Mad World, Simple Minds' Don't You Forget About Me and Little Mix's Woman Like Me which has had about 800m downloads

Sometimes, however, Knebworth saves filming fixtures and fittings from the skip.

The current state drawing room doors and panelling in the armoury, for example, came from the film Victoria and Abdul.

"We often find when they bring their amazing carpenters in and rework the rooms to their designs, that some of the things they come up with are rather better than what we've already got," Lord Cobbold said.

Dame Judi Dench and Ali Fazal in the gardens in Victoria and Abdul (2017)

Film money also contributes to repairs and conservation, which has made a "massive difference", the custodian said.

"We've been able to reupholster furniture and redo wallpaper and lots of things that we otherwise really wouldn't have a budget for," he said.

The house is also developing screen tourism attractions to capitalise on Hertfordshire's growing importance in the industry.

The Mrs Bulver Lytton Room has seen Spike MIlligan drinking milk in bed, been Mrs Thatcher's bedroom in The Crown and the scene of a murder in You

Deirdre Wells, chief executive at Visit Herts said money raised from production companies was "vital".

"With one in five tourists influenced by what they see on screen when making their destination choice, combined with the increasing demand for filming using UK destinations as the backdrop, there is huge potential for locations to develop screen tourism products," she said.

As for Knebworth, Lord Cobbold said: "We are always delighted when a film company comes along in October and tells us we could be a character in a new series.

"We've done about 90 movies here and we're looking forward to hitting our 100th and heading off into the next 100."