There’s apparently no truth to that story (or at least no evidence has been found) or to the legend that there was a secret tunnel which ran under the river from the mid-stream island to the nearby Bull’s Head pub on Strand-on-the-Green in Chiswick where Cromwell was said to have had established a headquarters (the tunnel was apparently so he could escape if the Cavaliers got too close).
The island, which stands in a stretch of the river between Kew and Chiswick (just upstream from Kew Railway Bridge and downstream from Kew Bridge) in London’s west, is not quite an acre in size (and, like Chiswick Ait, it’s roughly ship-shaped) but has served various purposes over the years.
In 1777, the City of London’s navigation committee built a wooden, castle-shaped tollbooth on the island with a barge moored alongside to catch passing river trade and so fund improvements to the navigability of the river. One story says it’s that barge that apparently lent its name to the delightful nearby pub, The City Barge, but others say the pub is named after the Lord Mayor of London’s State Barge which had winter moorings nearby for a time.
In 1865 a smithy was built on the island which was used in the building and repair of barges. It was later, after the Port of London Authority took over ownership in 1909, used as a storage facility and wharves for derelict vessels. The building survived until the 1990s but is now gone – along with any other signs of civilisation.
The island, which now has a dense canopy largely made up of sycamore trees, is these days inhabited by birds – those spotted there have included mallards, cormorants, Black-headed gulls, Canada geese, Egyptian geese, mute swans, magpies and robins – as well as a range of other life – a 2014 survey found 11 species of mollusc and 35 species of vegetation and the island has also been cited as a habitat for bats and Thames door snails.