While "bokken" are safer for sparring and practice than katanas, they are still lethal weapons in the hands of trained users. A famous legend to this effect exists involves Miyamoto Musashi, a ronin known to fight fully armed foes with only one or two "bokkens". According to the story, he agreed to a duel with Sasaki Kojiro at the early morning on Ganryūjima island, a tiny sandbar between Kyushu and Honshu. Musashi overslept the morning of the duel, however, and hastily made his way to the duel late. He carved a crude "bokken" from an oar with his knife while traveling on a boat to the duel. At the duel, Sasaki was armed with his large "nodachi", yet Musashi crushed Sasaki's skull with a single blow from his "bokken", killing him. While many elements of the story are likely apocryphal, the potential danger of a "bokken" from the legend is real.