Port Stephens is a large natural harbour located about 160 kilometres (99 mi) north-east of Sydney in New South Wales, Australia. It lies wholly within the Port Stephens Local Government Area (LGA) although its northern shoreline forms the boundary between the Port Stephens and Great Lakes LGAs. More than 26,000 people live within 3 km (1.9 mi) of its 113 km (70 mi) long shoreline and more than 32,000 live within 10 km (6 mi).
Port Stephens has a narrow entrance between two striking hills of volcanic origin. The southern headland, "Tomaree" or "South" Head, rises to 120 metres (390 ft) above mean sea level (AMSL) while "Yacaba", the northern headland, is 210 m (690 ft) AMSL. The harbour is mostly shallow and sandy but contains sufficient deep water to accommodate large vessels; the RMS Queen Mary moored there during World War II. After its recovery from the wreck site in 1974 the bow of the MV Sygna, a 53,000 tonne Norwegian bulk carrier that was shipwrecked on Stockton Beach earlier that year, was moored in Port Stephens, at Salamander Bay, for almost two years.
With an area of approximately 119 square kilometres (45.9 sq mi) Port Stephens is larger than Sydney Harbour. It extends approximately 24 km (15 mi) inland from the Tasman Sea and at its widest point, between Tanilba Bay and Tahlee, it is 6.5 km (4 mi) across. The narrowest point is between Soldiers Point and Pindimar where the distance is only 1.1 km (0.7 mi). Between Nelson Bay and Tea Gardens, in the most well known section of the port, it is 3.8 km (2.4 mi) wide.
The Karuah River drains into Port Stephens at its north-western corner. The Myall River (through the Myall Lakes) drains into the port on its northern shore, about 5.7 km (3.5 mi) from the mouth of the port. Twelve Mile Creek drains into the port's south-western corner.