Berkshire (, abbreviated Berks, in the 17th century sometimes spelled Barkeshire is a county in south east England, west of London and is one of the home counties. It was recognised by the Queen as the Royal County of Berkshire in 1957 because of the presence of Windsor Castle, and letters patent were issued in 1974. Berkshire is a county of historic origin and is a home county, a ceremonial county and a non-metropolitan county without a county council.
The historic boundary to the north of Berkshire follows the River Thames, from Buscot to Old Windsor. Therefore, the historic county includes territory that is now administered by the Vale of White Horse and South Oxfordshire districts of Oxfordshire, but excludes Slough and Eton, which are historically in Buckinghamshire.
Wikipedia https://en.wikipedia.org/wiki/Berkshire
Coordinates 51°27'1.943" N -1°4'20.361" E