Almost £1 million is needed to save a historic Grade II listed building.

Cobham Dairy has suffered so much decay over the years that it is now close to being beyond repair, and has been placed on the national Buildings At Risk Register.

Situated in the grounds of what is now independent girls’ school Cobham Hall, the building was commissioned by the fourth Earl of Darnley for his wife Elizabeth Brownlow.

The supervision of the making of cream and butter was once considered a fashionable pursuit for aristocratic women, with the likes of the ill-fated Queen of France, Marie Antoinette, also having an ornamental dairy built.

Architect James Wyatt and landscape designer Humphry Repton were given the task of making it a reality in 1794, but by the time the school was opened in 1962 it was already derelict, and has remained so ever since.

It has been re-roofed and boarded up, but now the Landmark Trust is hoping to raise £954,000 to fund a more permanent and extensive restoration.

Trust director Dr Anna Keay said: “Cobham Dairy is a rare and fragile survivor.

“It is uniquely captivating, both as a miniature masterpiece by a brilliant architect, but also a window onto the hidden world of 18th century women.

“Today it stands in ruins, with graffiti on the walls, boarded Gothic-arched windows, collapsing plaster vaulting, and its exterior stripped bare of slate.

“It is uniquely captivating, both as a miniature masterpiece by a brilliant architect, but also a window onto the hidden world of 18th century women," - Dr Anna Keay

“Once lost, such precious heritage cannot be retrieved.”

Rescuing the 220-year-old building will demand detailed historical research, careful conservation decisions, and specialist craft skills.

Mr Wyatt’s original drawings still survive at the Yale Centre for British Art to aid the project, which aims to return the building to its original appearance.

The project will add a bathroom, bedroom, and sitting room, but the exterior’s old cut slate cladding will be replicated to give the building the same crisp, white appearance it boasted in its prime.

Apprentices will be brought on board to assist and heritage insurance firm Ecclesiastical Insurance has pledged £1 for every £1 donated over the next six months, up to a maximum of £200,000.

The company’s chief executive, Mark Hews, said: “Ecclesiastical is a special kind of business, giving back to the communities with whom we do our business.

“As heritage specialists in the insurance world, I am delighted we are partnering the Landmark Trust in saving this important building for the nation and at the same time supporting the specialist craftsmen and women who will benefit from applying their skills in a high-quality restoration project.”

School bursar David Standen said: “We are delighted the Landmark Trust has taken on the restoration of this important building and that it will have a positive use in the future.

“The dairy is the final piece of the jigsaw puzzle as it is the last building in Cobham Park that requires restoration.”

Donations can be made here.