Oakley is a district of Cheltenham in Gloucestershire, England. It is home to the smaller of Cheltenham's two GCHQ sites, and residential housing including private, council-owned and social housing. It backs onto Cleeve Hill and Harp Hill, greenbelt land and part of the Cotswold hills, including a covered reservoir. Oakley neighbours Prestbury and Whaddon. In the early 2000s, part of the GCHQ Oakley site was reclaimed and replaced with a Sainsburys supermarket. In the Domesday Book of 1086 it is recorded as held by Turstin FitzRolf.