In the 18th century, Society Hill was home to wealthy merchants and many members of the federal government. In Old City, artisans and workmen lived and worked in small row houses like those on Elfrerth's Alley. As Philadelphia developed, it abandoned its Colonial center. Almost forgotten by 1900, Society Hill had become home to poor immigrants and its once gracious houses had become run-down tenements, shops, and warehouses. Yet, at the same time,...