The SS New Guinea was built by W. Doxford and Sons at Sunderland and launched on 7 October 1884: an iron, single-screw steamer of 2,674 tons, 300 feet long and 40 feet wide, with a 260 hp compound engine and two masts. Built for McIlwraith, McEacharn and Company of Melbourne, she worked on the London–Australia run and later the Australian coast. On 13 February 1911, under charter to Huddart Parker on a voyage from Melbourne to Sydney, she ran into dense fog near Green Cape and at 11.50 am went aground exactly 1.25 km west of the lighthouse. The engine was put astern, but too late; the engine room and bow flooded, and the 28 crew took to the boats, eventually reaching Eden. Within two days she had broken up. A Marine Court of Inquiry found Captain Coleman at fault for being too close inshore at full speed in thick fog. In the 1960s salvors used explosives on the wreck, and it was also heavily 'ratted'.

Today the wreck lies in less than 10 m, mostly between two ridges that run from the cliff into the sea. McFadyen describes the keel and large sections of hull still intact with plating and supports everywhere. Among the most interesting items are two huge detachable propeller blades, carried as cargo and bolted together for storage, and dozens of square lead ingots with central holes. Boiler pieces are scattered through the area. The prop shaft runs west over the next ridge past three more cargo blades to a large bearing and on to the ship's own four-bladed propeller, all its blades snapped off at the stubs – consistent with the engine going astern as she struck. The Marine Life Network calls it a very interesting jumble of iron.

Boat access only and rarely dived. Green Cape is about 28 km by sea south of Eden, a long exposed run from the Quarantine Bay ramp that is only sensible on a settled forecast. Small boats more often launch at Wonboyn Lake, but the lake entrance and bar are shallow and can only be crossed within about two hours either side of a high tide of 1.8 m or more, so a trip needs a morning high tide and no southerly swell.

At the site, the cliff to the north has distinctive saucer-shaped rock layers whose ends run into the sea as ridges; wreckage, including an anchor, is visible on shore inside the western ridge. A small bombora lies to the east, and you should be on a line between the lighthouse to the east and a prominent cave to the west. Anchor on top of the western ridge.

Being under 10 m deep, the wreck can only be dived in extremely calm seas (McFadyen); the Marine Life Network calls it unapproachable in all but perfectly calm weather. It is protected from some winds, especially north-easterly and easterly, but any southerly swell rules it out. Plan around the Wonboyn bar tide window (about two hours either side of a morning high tide of 1.8 m or more).

From the western ridge, work the area between the two ridges: keel, hull plating and supports, two large detachable propeller blades bolted together, dozens of lead ingots and boiler pieces. Follow the prop shaft west over the next ridge past three more blades to a large bearing and on to the ship's four-bladed propeller with its blades broken off.

Protected under the Underwater Cultural Heritage Act 2018.

McFadyen notes local charter operators generally do not dive the Green Cape wrecks because of the distance (about 28 km from Eden); Merimbula Divers Lodge may organise group trips in suitable weather. Mostly private boats from Wonboyn.