Quite a good surface on the main GU canal, OK on the Slough branch. Would come off at Uxbridge, go through the town and up Belmont Road, signed cycle route left into Fairfield Road, right into Norfolk Road, along the south side of Uxbridge Common, cross Park Road at the Toucan Xing, left onto the separate cycle path, turn right next to the traffic lights onto the path that takes you over the A40, through Swakeleys Park to Ickenham and thence Ruislip.