The Gap is an ocean cliff located in the eastern suburb of Watsons Bay, near South Head. The Gap is also a suicide location of some notoriety, with a reported 50 suicides annually. It was reported that new security cameras, emergency telephones and higher fences will be erected in an attempt to reduce the suicide rate.

In 1857 the sailing ship Dunbar carrying 63 passengers and 59 crew crashed into the rocky cliff at the foot of The Gap. Dunbar, captained by James Green, left England on 31 May 1857 and arrived off Botany Bay shortly after dark on 20 August 1857. The weather was stormy, with a strong wind blowing. In poor visibility, Captain Green misjudged the entrance to the harbour and, almost before anyone on board knew what was happening, the Dunbar sped into the great rocky cliff at the foot of The Gap. The impact was so violent that the topmasts snapped like matchwood. Waves turned the stricken ship broadside on pounding her asunder against the rocks.

The next day grieving crowds watched helplessly as breakers pounded victims corpses against the rocks, while inside the harbour the incoming tide carried naked bodies, many shockingly mutilated by sharks, amid nests of cargo and wreckage.

Miraculously, one man survived, a young sailor named James Johnson, who clung to a rocky ledge below the Gap for 36 hours. James later employed at the Newcastle lighthouse rescued another lone survivor from the wreckage of the steamer, SS Cawarra in July 1866.

The funeral of the Dunbar victims was the longest procession Sydney had ever seen. The unidentified dead were buried in a common grave at Camperdown cemetery. The Dunbar's anchor was recovered more than fifty years later and placed on the cliffs at Watsons Bay with a memorial tablet.