This one requires you to ride the line as a passenger for 20 miles looking out of the window. Any external camera time doesn't count towards the achievement! Should be just over 2 runs up or down the line to complete. Pick a service from the timetable, go into explore on foot to start at Shanklin or Ryde Pier Head at a time 3 minutes before the service starts eg. 10.35 for the 10.38 service from Shanklin to Ryde Pier Head and restart when the service finishes if you use a wireless controller then it would be a good idea to plug it into your console and you can go and do something else and just leave the game to run up and down the line until the cheevo pops. If you haven't got the walk 100 miles achievement then you can fill the waiting time with a walk up and down the platform.