A narrowboat travels at around 4 miles per hour but it's important to slow down from that heady speed when passing moored boats. On a really wide stretch of river, speed-freaks can go wild and crank things up to 6 mph. Here, Mac is in the process of over-taking another narrowboat going a little too slowly for his liking. This high-octane, nail-biting manoeuvre took about twenty minutes! You can almost feel the G-force!
