This chart of the River Thames Estuary features the northern part of the Isle of Sheppey on the south of the Estuary, and Southend-on-Sea and Foulness Island on the north of the estuary. The Isle of Sheppey is situated in the Thames Estuary off the northern coast of Kent. It lies 46 miles east of London. The island is separated from the mainland by a channel called The Swale. The largest town on the island is Sheerness which is located on the northernmost point. On the other side of the River Thames is Southend-on-Sea and Foulness Island. Southend lies in Essex and is separated from Foulness Island by narrow creeks. The chart is set on a blue background and is finished with a white mount and frame combination.