Detroit is 71% larger than Cincinnati.
Area: 224 km2 calculated
Cincinnati is the third largest city in Ohio and the 28th largest city in the United States by metropolitan population and the county seat of Hamilton County. Settled in 1788, the city is located on the border between Ohio and Kentucky at the confluence of the Ohio River and the Licking River. Wikipedia
Area: 383 km2 calculated
Detroit is the most populous city in the U.S. state of Michigan and the largest city on the United States-Canada border. It is the seat of Wayne County, the most populous county in the state. Wikipedia