In a popular American song by Stephen Foster, how long is Camptown racetrack?

"Camptown Races" is a catchy tune and one that you probably remember from childhood. You may even have taught your own children how to sing it. Written by preeminent American songwriter Stephen Foster (1826–1864) in the mid-1800s, the song has long been a favorite among American folk songs, and the first verse is a definite earworm:

"De Camptown ladies sing this song,

Doo-da, Doo-da

De Camptown racetrack's five miles long

Oh, doo-da day"

Camptown in Pennsylvania, near Foster's hometown, is thought by some to be the inspiration for the song, though the Pennsylvania Historical and Museum Commission cannot say for certain whether there was a racetrack in or near the city or its length. Other sources say that there were horse races from the city to Wyalusing, Pennsylvania, about five miles between each city center. Others believe the song refers to "camp towns," established by transient workers near railroads. Or it could be all of the above.