The Falkirk Wheel is a unique and innovative way to get boats from one canal to another. The official site describes the history. “The Forth and Clyde Canal is 35m (115ft) below the level of the Union Canal. Historically, the two canals had been joined at Falkirk by a flight of 11 locks that stepped down across a distance of 1.5km, but those were dismantled in 1933, breaking the link. What was required was a method of connecting the two canals by some means of lifting two boats down the 35m drop as quickly and simply as possible.” I found some good pictures of the contraption at a russian blog, and there are some YouTube videos of the wheel in action.