A building on Tremont Street. The South End was created in the 1840s by landfill, on what was a narrow isthmus connecting Boston to the mainland. In the 1850s, according to the South End Historical Society, London-style squares with brick bowfront town houses were built to attract the mercantile class. Soon after, commercial avenues like Columbus were built in a Parisian boulevard style. After suffering from neglect, arson, and economic setbacks through the 1970s, the area blossomed into a highly desirable place to visit and live.