A museum to commemorate the role an ex-RAF base played in the Battle of Britain will open next year after winning a grant of £650,300.

Bentley Priory Museum, in the grounds of the grand country house in Stanmore, will be transformed into a museum and learning centre to tell the story of the building’s key role in preventing the Nazi Luftwaffe from destroying Britain’s air force during the Second World War.

The £650,300 grant from the Heritage Lottery Fund will be used to fit out the museum and carry out specialist conservation work on the Grade II* listed building, where RAF Commander Sir Hugh Dowding directed his men during the 1940 campaign.

The project will also recruit volunteers to run the museum in the former Officers’ Mess, ranging from tour guides to tending for the Italian gardens, securing the future of the site which closed as an RAF base in 2008.

Chairman of the trustees of the Bentley Priory Battle of Britain Trust, Air Chief Marshal Sir Brian Burridge, said: “We have worked hard for seven long years to provide a sustainable future for Bentley Priory that befits its enormous significance.

“Many would say that if the Battle of Trafalgar saved England, the Battle of Britain saved the world. 

“We are delighted that the Heritage Lottery Fund has endorsed our plans with this award.  We now look forward to fitting-out the museum and telling the important stories of the priory to a broad audience.”

Last year, the Prince of Wales launched a £1.8 million appeal to save the airbase by becoming a patron of the trust and bring the museum plans to fruition.

The queen mother, Prince Charles’s grandmother, was a frequent visitor to the air base during the Second World War, as well as Winston Churchill.

The Prince’s Regeneration Trust, one of the Prince’s charities, played a key role in work with Barratt Developments and the City & Country Group on the development of the homes on other parts of the site.

A series of open days, starting in 2008 with the backing of the Harrow Times, has seen thousands explore its grounds.

The trust says it will work with community groups and charities to offer a venue for their activities and provide work experience opportunities, as well as opening the museum up for schools to visit.

The house, originally built in 1766, was significantly extended in 1788 by Sir John Soane, one of the most important architects of the period, and had a long history as a Royal palace when Queen Adelaide, the widow of William IV and aunt of Queen Victori, lived there from April 1846 until her death in 1849.