The Rock Island Arsenal comprises 946 acres (383 ha), located on Arsenal Island, originally known as Rock Island, on the Mississippi River between the cities of Davenport, Iowa, and Rock Island, Illinois. It lies within the state of Illinois. Rock Island was previously used as the summer camp site for Sauk Native Americans, and the dispute over tribal ownership led to the Black Hawk War of 1832, after the primary leader of the Sauk, Black Hawk. It is now home of First Army headquarters, and the US Army's Center of Excellence for Additive Manufacturing. https://en.wikipedia.org/wiki/Rock_Island_Arsenal