Abbey River Tideway where there are two larger islands. It is much smaller than Canvey Island and the Isle of Sheppey and narrowly ahead of Andersey Island facing Abingdon-on-Thames, another market town with an abbey which had multiple medieval mills, another of note being Westminster Abbey, the island of which Thorney Island no longer exists. The outfall of the Abbey River is 400 m above Chertsey Bridge, into the weir pool of Chertsey Weir. The manmade strictly-considered "island" the bypass channel forms is outranked in size since the 2002 completion of the Jubilee River by the example containing Dorney and Eton, Berkshire.
Canvey Island the present island, with a ditch being the current boundary, having the same far eastern points as the Canvey Point and Leighbeck Point marshes. Two Tree Island to the north is also recognisable, if halved in length. The third eastern island or mudflat could well be the Counus i.e. "council" Island where the Trinovantes, Cantiaci and the Catuvellauni counselled with the Iceni, shortly before staging Boudicca's rebellion against the Romans. If so Counus occupies an area from the Canvey Point Sand Bank until just before Shoeburyness, the eastern point of the relatively straight estuary so stretched the whole length of