City of the Iron Fish is a fantasy novel by English science fiction and fantasy author Simon Ings. It was first published in July 1994 in the United Kingdom as a paperback original by HarperCollins. The book is about an isolated City bounded by nothing that transforms itself every 20 years through magic evoking rituals. The novel has been compared to Mervyn Peake's Gormenghast (1950), and M. John Harrison's fictional city Viriconium. Ings said that he wrote City of the Iron Fish in six weeks while in a brothel in Oporto, Portugal, "on the run from my reputation as a cyberpunk writer".