Sonning Eye is a hamlet and island in the Thames in Oxfordshire, England; It is part of the Civil Parish Eye & Dunsden and has been the southernmost point of Oxfordshire since 1974. Until 1866, Sonning Eye was part of the otherwise located in Berkshire Sonning Civil parish. Sonning Eye is located opposite the village of Sonning in Berkshire, with which it is connected to the Sonning Bridge along with the Sonning Backwater Bridges.