For those of you interested in multisports, my running club (Serpentine) are organising a duathlon in Hyde Park (Central London) on 31st October.
It's basically 7.5k run/18.2k bike ride/4k run
Distances are fairly manageable and a good introduction to anyone starting out at this sort of thing.
For the more experienced duathletes this would be a fast race and probably good speed training.
More info can be found on http://www.serpentine.org.uk/events/duathlon/
Entries only opened this week and are limited to 100 so if you want to take part enter soon. (On line entry available).
I will be there - either marshalling or racing.