The Chatham Arch Historic District exhibits both historical and architectural significance. Its irregular street pattern, most of it dating before the Civil War, recalls life in Indianapolis when the city was just beginning to expand beyond the original Mile Square plat. The area also boasts a group of Civil War era workers’ cottages on Arch, St. Clair, and 9th Streets. These houses represent the working person’s presence in the early stages of Indianapolis’ growth into an industrial metropolis. Only a few pockets of these 1860’s and early 1870’s cottages survive in the downtown.