W4R3 completed. Not too bad (inspired by davidhwynn) although as expected the knees are beginning to complain. The dilemma is next week...I'm in Nottingham, central London, Reading and Leeds. I've identified a route in Nottingham but it's tomorrow. Is 36 hours long enough or do I risk a five day break? I'm not keen to do that, nor to pound pavement in the dark in London (or even park in the dark).