Where does Stephen King's "IT" take place?

The story behind the answer

Stephen King’s IT is set in the fictional town of Derry, Maine, where the Losers’ Club battles the shape-shifting entity Pennywise. Derry’s sewers, the Barrens, and the town’s eerie history are central to the plot, making Derry—not Texas, Illinois, or Lovecraft’s Innsmouth—the correct setting.

Context helps: King often places his stories in Maine (his home state), using recurring towns like Derry, Castle Rock, and Jerusalem’s Lot. Derry is loosely based on Bangor, Maine, and reappears in other King works. A handy memory trick: “King reigns in Maine—Derry is his scary town.” Also, Innsmouth is a well-known H. P. Lovecraft setting, not King’s, which helps differentiate the options.