Sydney Harbour is the 10-mile long Y-shaped inlet of the Atlantic, oriented southwest-northeast on the northeast shore of Cape Breton Island, Nova Scotia, Canada. At its upper reaches, the harbour forks to form 2 arms, the Northwest Arm and the South Arm. The South Arm is fed upstream by the Sydney River. Sydney Harbour is the maritime hub for the Cape Breton Regional Municipality. The South Arm affords year-round ice-free deep-water anchorage for large ships, including cruise ships.