Harrison Township established 1850, formerly part of Crosby Township. Among the historic sites in the city's vicinity is the Eighteen Mile House, which was built during the earliest years of the nineteenth century. Harrison was named after the 9th US President, William Henry Harrison. It was incorporated in 1850, and became a city in 1981. Harrison is a city in Hamilton County, Ohio, United States. The city is located in the Cincinnati-Northern Kentucky metropolitan area. The population was 7,487 as of the 2000 census. It was the home of Ohio's fifth governor Othneil Looker.