Ride along roads as close as practicable following the route of the non-tidal reach of the Thames from Teddington to the source. Great day's ride. Overcast with little wind, but very murky visibility. Really interesting and pretty first part but latter parts were at times pretty boring visually, nothing like the Thames itself which is lovely and wild further upstream. Gear issues meant I had to do the last 60 odd miles in the big ring (thankfully the big hills were over by this time), actually I got used to it and rather enjoyed it. Dave turned up 1/2 hour late so we were always chasing the clock to finish in time to catch our train. Made it with enough time for a pint before boarding. Excellent epic day out.