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You’ve got just over two weeks to make it to the John Henry celebration in Leeds, Alabama, where some folks believe the legendary steel driving contest actually took place. Maybe you already made it to John Henry Days in Talcott, West Virginia (or read a fictionalized account), where some more folks claim the same. John Garst, Scott Nelson, and other folklorists weigh in here, supplemented by a wealth of links and resources on the subject. While you think on it let Mississippi Fred McDowell, The Boss, Ralph Stanley, John Jackson, Merle Travis, and Jason Isbell tell their own versions.
John Garst and his research mentioned previously.