The island is a barren outcrop of bedrock, with a permanent size of half an acre rising to only three feet above sea level, plus an intertidal zone of a further 5 acres (20,000 m2).
On a 1775, London chart, this island was labeled Hayman's Island and shows a greater area than presently exists.
There is no historical evidence that this island was used as a location for hanging criminals.
During the American Civil War, targets were placed on the island for artillery practice for troops training at Camp Adams.
[3] In 1882, several fishermen built fishing shacks on Hangman Island and were reported to have cultivated a vegetable garden among the rocks.