Posted: 23/06/2015 at 15:09
We did it in 2012 - didn't need much water as it was rather cold, but I seem to remember there was plenty available. It was friendly enough and a good route, but took ages to get going (we saw the winner cross the line on the big screen before we'd got past the start). You shouldn't be left behind, but be prepared to hang around a lot.
Good luck, hope you enjoy it.