Innsmouth, Massachusetts

An almost-deserted fishing town in Massachusetts. It was once dominated by degenerate Cthulhu cultists, led by the evil Obed Marsh and his Esoteric Order of Dagon church. For decades, they held the town for ransom, murdering their foes and perverting their servants with blasphemous religious rites and unholy unions with the amphibious deep ones.

Since the government raided the place and torpedoed the reef offshore back in 1928, it's been nothing more than a decaying, rotting, legend-haunted ghost town, stinking of fish and sin.

"The Shadow Over Innsmouth" by H.P. Lovecraft
Encyclopedia Cthulhiana by Daniel Harms, pp. 102-103

H. P. Lovecraft's Innsmouth is based on the old city of Newburyport, Massachusetts. At the time Lovecraft visited the city it was in run down in some areas with an abandoned look. The salt marshes up and down the coast also give the city a feel of being separated from anywhere else. Innsmouth is supposed to be halfway between Newburyport and Arkham.

I certainly hope you can get to see Newburyport sooner or later, for its antiquity and desolation make it one of the most spectrally fascinating spots I have ever seen.
- H.P. Lovecraft 11/20/1931

Newburyport is exactly as it was in colonial times a study in colourful stagnation. At sunset today a marvellous silver mist rolled in from the sea, giving everything an antique and ethereal glamour.
- H.P. Lovecraft 8/30/1927