The Britannia Yacht Club (BYC) is a private social club, yacht club and tennis club based in Britannia, Ottawa, Ontario, Canada. It was founded in 1887 by a group of cottagers. BYC is located on an extension of land at the eastern end of Lac Deschênes near the Deschênes Rapids on the Ottawa River. A land block owned by the National Capital Commission on the south side of the harbour is leased to the BYC. The area immediately south of the property is occupied by residences of Britannia Bay. The harbour was built from an abandoned power canal, which lay beside the club property. This harbour has been expanded twice since its original development. The harbour water level is controlled by a system of stop logs at its entrance.