South Arm is the southern branch of Sydney Harbour, a major saltwater inlet on the east coast of Cape Breton Island, Nova Scotia. This sheltered arm of the harbor is a significant industrial and commercial port area, home to facilities like the International Coal Pier, Atlantic Canada Bulk Terminal, Sydport, and the Sydney Marine Terminal. It is a deep-water harbor with a controlling draft of 11.58 meters in the main shipping channel, extending inland from the bifurcation at Point Edward. The western shore features the private Dobson Yacht Club at Dobson's Point, while the area is exposed to northeasterly winds. As a working harbor, it presents a unique blend of industrial infrastructure and marine habitat for anglers targeting inshore saltwater species.