10 miles of track laid in one day

cprr.org/Museum/Southern_Pacific_Bulletin/Ten_Mile_Day.html

FIFTY-NlNE years ago a squad of eight Irishmen and a small army of Chinese coolies made a record in track laying that has never been equalled. In one day, on April 28, 1869, these men, fired with the enthusiasm of the greatest railroad construction race in the history of the world, laid ten miles and fifty-six feet of track in a little less than twelve hours to bring the railhead of the Central Pacific three and one-half miles from Promontory, Utah, where connection was made a few days later with the Union Pacific to form the first transcontinental railroad.