TypeBayDetailsOn the northern side of the entrance to Yeomans Bay which is an arm of Cowan Creek. Usually known as Castle Lagoon. High on the southern entrance to the bay is a rock formation rather like a row of battlements and the name may well be associated with this.CreatorPowell, John P. 1994, Placenames of the Greater Hawkesbury Region, Hawkesbury River Enterprises, Berowra, p.21
Powell, John P. 1994, Placenames of the Greater Hawkesbury Region, Hawkesbury River Enterprises, Berowra, p.21, Castle Bay. Hornsby Shire, accessed 26/04/2026, https://hornsbyshire.recollect.net.au/nodes/view/4482