Character mistake: Red says that Andy crawled to freedom through 500 yards - 'just shy of half a mile'. 500 yards is far less than half a mile; in fact, it's less than a third of a mile. It is however just shy of half a kilometer, which may be what King was thinking of when he wrote the book.
Character mistake: When Fred and Barney are about to be hanged, Betty and Wilma are in the car on their way to save them. Betty calls Wilma 'Willa' instead of Wilma. (01:09:00)