title: RAF Bentley Priory
context: The station incorporated Bentley Priory, which was originally built in 1766. The house was significantly extended in 1788, by Sir John Soane, for John Hamilton, 1st Marquess of Abercorn. It was the final home of the Dowager Queen Adelaide, queen consort of William IV, before her death there in 1849. Afterwards the building was used as a hotel and girls' school before being acquired by the RAF in 1926. The site includes a Grade II* listed Officers' Mess and Italian Gardens. These, together with the park, are designated a Registered Garden Grade II. The land south of the house is the Bentley Priory Nature Reserve, a Site of Special Scientific Interest maintained by Harrow Heritage Trust.[3]
question: How old is RAF Bentley Priory?
answers: built in 1766