Thames Estuary The new airport would be built on a man-made island in the estuary north of Minster-in-Sheppey There is also some discussion about the need for a Lower Thames Crossing in order to alleviate traffic congestion at Dartford. The Thames Estuary is the focal part of the 21st-century toponym, the "Thames Gateway", designated as one of the principal development areas in Southern England. The appellation Greater Thames Estuary applies to the coast and the low-lying lands bordering the estuary itself. These are characterised by the presence of mudflats, low-lying open beaches and salt marshes, namely the North Kent Marshes and the
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