Innsmouth, Massachusetts (/ˈɪnzməθ/) is a fictional town created by American author H. P. Lovecraft as a setting for one of his horror stories, and referenced subsequently in some of his other works and by other authors who wrote stories taking place in the world Lovecraft created with his stories.
Lovecraft first used the name "Innsmouth" in his 1920 short story "Celephaïs" (1920), where it refers to a fictional village in England. Lovecraft's more famous Innsmouth, however, is found in his story "The Shadow Over Innsmouth" (1936), set in Massachusetts. This latter Innsmouth was first identified in two of his cycle of sonnets Fungi from Yuggoth. Lovecraft called Innsmouth "a considerably twisted version of Newburyport", Massachusetts.
Lovecraft placed Innsmouth on the coast of Essex County, Massachusetts, south of Plum Island and north of Cape Ann. The town of Ipswich, Massachusetts is said to be a near neighbor, where many Innsmouth residents do their shopping; Rowley, Massachusetts, another neighboring town, is said to be to the northwest. This would place Innsmouth in the vicinity of Essex Bay.