Black Boy Island

Black Boy Island is an uninhabited island in the River Thames in England between the villages of Medmenham, Buckinghamshire and Hurley, Berkshire. It is situated alongside the small hamlet of Frogmill, on the southern side of the stretch of river above Hurley Lock, and is within the Royal Borough of Windsor and Maidenhead unitary authority.

The island is very low-lying, such that it is covered with water whenever the Thames floods. It is now heavily wooded, but up until the 1920s it and the adjacent Frog Mill Ait were without vegetation. This was because the towpath was (and still is) on the southern side of the island whilst the boats being towed along by horses had to keep to the main navigation channel on the northern side of the river. The tow lines had to sweep over the islands, and the angle of tow was such that barges could be pulled aground onto the islands.