The island is located between Hedsor Water and the present navigation channel leading to Cookham Lock.
[2] The island is believed to have been at the point where the Thames was crossed by a Roman road called Camlet Way, which ran from St. Albans to Silchester.
Wooden piles and stakes were found here in the nineteenth century and again in 1969 which may indicate the remains of a substantial bridge.
[3] In Saxon times, Sashes Island was the site of a burh built under Alfred the Great as a defence against the Danes.
No trace of this burh has been found, but this may be as a result of the digging of the lock cut in the 1830s, which disrupted the terrain.