Great Cob Island
Great Cob island is a small island in the estuary of the River Blackwater in Essex, England, the United Kingdom. The island is an area of low-lying salt marsh in the tidal channel known as Virley Channel that runs to the east of the village of Tollesbury. Long and narrow in shape, it is around in length and around at its widest. It lies just to the south of the RSPB nature reserve of Old Hall Marshes.