Keene is a city in Cheshire County, New Hampshire, United States. The population was 23,047 at the 2020 census, down from 23,409 at the 2010 census. It is the county seat and the only city in the county. Keene is home to Keene State College and Antioch University New England. It hosted the state's annual pumpkin festival from 1991 to 2014, several times setting a world record for most jack-o'-lanterns on display. The grocery wholesaler C&S Wholesale Grocers is based in Keene.