Cincinnati (Wikipedia) Cincinnati (/ˌsɪnsɪˈnæti/ SIN-si-NAT-ee) is a city in the U.S. state of Ohio and the county seat of Hamilton County. Settled in 1788, the city is located at the northern side of the confluence of the Licking and Ohio rivers, the latter of which marks the state line with Kentucky. The city is the economic and cultural hub of the Cincinnati metropolitan area. With an estimated population of 2,256,884, it is Ohio’s largest metropolitan area and the nation’s 30th-largest, and with a city population of 309,317, Cincinnati is the third-largest city in Ohio and 64th in the [United States](United States). Throughout much of the 19th century, it was among the top 10 U.S. cities by population, surpassed only by New Orleans and the older, established settlements of the United States eastern seaboard, as well as being the sixth-most populous city from 1840 until 1860.