HMS Ontario was a British warship that sank in a storm in Lake Ontario on October 31, 1780, during the American Revolutionary War. She was a 22-gun snow, and, at in length, the largest British warship on the Great Lakes at the time. The shipwreck was discovered in 2008 by Jim Kennard and Dan Scoville. The Ontario was found largely intact and very well preserved in the cold water. Scoville and Kennard assert that "the 80-foot sloop of war is the oldest shipwreck and the only fully intact British warship ever found in the Great Lakes."