[1] Mill Hill Barracks, a set of red brick buildings designed by the architect Harry Bell Measures CBE MVO (1862–1940), was built in 1904 on the site of Bittacy farm.

[2] On 31 October 1962, shortly after the occupation of the barracks by Home Postal & Courier Communications Depot RE, Mary, Princess Royal and Countess of Harewood, as the Controller Commandant Women's Royal Army Corps (WRAC) laid the foundation stone for extra barrack blocks[9] to be built within the site to accommodate 12 Company, WRAC.

[15][16] The Prime Minister, Margaret Thatcher, subsequently met officers to offer her condolences as the barracks bordered her then Parliamentary constituency.

The military presence at the barracks ceased in 2007 and Ministry of Defence sold the site for residential development as part of Project MoDEL in 2012.

[1] Sixty years later the Duke of Windsor's niece, The Queen, unveiled a life-size statue entitled Letter from Home, which stood outside the Guard Room, on her visit to the barracks in 1982.

The statue was moved to RAF Northolt when the barracks were vacated by the British Forces Post Office (the successors of the Home Postal Depot RE) in 2007.

The statue was simply called Soldier Reading a Letter and was erected as a memorial to the men and women of the Great Western Railway who lost their lives during the First and Second World Wars.