You know you are half way when you hit Tower Bridge before the long slog through Docklands and Canary Wharf, made easier in recent years by redevelopment, but somewhere I remember as being desolate back in 1997.
Then it’s on to the Embankment as you turn for home. I hope Sunday’s runners are not hit by the hail-storm we faced in 2009 they can then enjoy – unlikely I accept with your body aching - the last four miles as the realisation dawns that they are going to make it!