The SS Glenlyon is a shipwreck off Isle Royale in Lake Superior, where a once-innovative Great Lakes freighter now rests near Menagerie Island and the Isle Royale Light. Built in 1893 as the William H. Gratwick, later renamed Minnekahta and then Glenlyon, it served under several owners in both the United States and Canada before running aground in stormy weather on November 1, 1924, after leaving Thunder Bay with wheat. Most of the crew were rescued, but the ship could not be saved and soon broke apart and sank. Preserved in cold water, the wreck remains an important archaeological site and a rare surviving example of a transitional Great Lakes freighter.