Cairo is the southernmost city in the U.S. state of Illinois and the county seat of Alexander County. The city is located at the confluence of the Ohio and Mississippi rivers. Fort Defiance, a Civil War camp, was built at the confluence in 1862 by Union General Ulysses S. Grant to control strategic access to the river. Cairo has the lowest elevation of any location in Illinois and is the only Illinois city to be surrounded by levees. It is in the... Show more

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