Q: "A 'camptown' was a temporary workingmen's tent or shank settlement. According to Wikipedia, Foster's 'camptown' was in Pennsylvania.

Camptowns grew and were dismantled as the railroads moves west, and with other longer term construction projects."

Foster's "camptowns" were even more temporary and transient "shinbone alleys" than this.

They were the tent cities in the infields of a race track. The same locations were used by the circus when it came to town. Typically a semi-permanent "fairground" across the river or on the outskirts of town because… "g'wine to run all night…."

There were "booths as at a fair, where everything was said, and done, and sold, and eaten or drunk – where every fifteen or twenty minutes there was a rush to some part, to witness a fisticuff - where dogs barked and bit, and horses trod on men's toes, and booths fell down on people's heads!"

Carlyon, Dan Rice (New York: Perseus, 2001, p.29)

Urban sprawl would have long since paved over (twice) anything on the outskirts of an 1840-50 American city or large town.