There is hereby designated as an environmentally sensitive area the area of land in the valleys of the Upper Thames and its tributaries in the Counties of Buckinghamshire, Gloucestershire, Northamptonshire, and Oxfordshire which is shown coloured yellow on the maps contained in the volume of maps marked “volume of maps of the Upper Thames Tributaries environmentally sensitive area” dated 3rd March 1994, signed and sealed by the Minister and deposited at the offices of the Ministry of Agriculture, Fisheries and Food, 17 Smith Square, London SW1P 3JR.