The Flatt & Scruggs reading — clipped vocal phrasing over Scruggs’s three-finger banjo and a hard-charging tempo — is what most pickers cover today. The song belongs to a small family of mid-century bluegrass train pieces (alongside “Orange Blossom Special” and “Wreck of the Old 97”) that translate the rhythm and forward motion of a steam train into a vocal-and-banjo showpiece.

Lyrically the narrator boasts about a fast mail train barrelling out of Georgia — an unselfconscious celebration of speed and the romance of rail in the era when mail-by-train still defined how news and money moved across the South. It remains a jam-friendly standard at bluegrass festivals, generally taken at a brisk tempo with a banjo-led break out of the kickoff.