As a result, most of Isleworth's riverside is that part overlooking the 8 acres islet of Isleworth Ait: the short-length River Crane flows into the Thames south of the Isleworth Ait, and its artificial distributary the Duke of Northumberland's River west of the Isleworth Ait, one of two Colne distributaries constructed for aesthetic reasons in the 1600–1750 period.