Chiswick Eyot Chiswick Eyot Chiswick Eyot is a narrow, uninhabited ait (river island) in the River Thames. It is a tree- and reed-covered rise on the Tideway by Chiswick, in the Borough of Hounslow, London, England and is overlooked by St Nicholas Church, Chiswick, the Mall (promenade street) of Hammersmith and by some of the Barnes riverside on the far bank. Excluding tidal mudflats and sandbanks, it is the most downstream island purely on the Thames itself (as the Isle of Sheppey, Canvey Island and two nearby islets in the estuary are co-fed by creeks and in the case of Sheppey by
Severn Estuary the line between Lavernock Point and Sand Point is the Bristol Channel, which in turn discharges into the Celtic Sea and the wider Atlantic Ocean. The islands of Steep Holm and Flat Holm are located close to that line, in the middle of the estuary. Sometimes the term "Severn Estuary" is used to include the tidal upstream stretch between Gloucester and Aust. During the highest tides on the upper reaches of this stretch, the rising water is funnelled up the estuary into the Severn bore, a self-reinforcing solitary wave that travels rapidly upstream against the river current. The tidal range