Hi Cathy. The race is held at Friday Woods. In the past the event has started at 11:00, although there is no time mentioned this year, I think it is unlikely to have changed since last year.
The event is organised by Colchester Rovers Cycle Club and Colchester Harriers Running Club. The format is as follows. The cyclists complete 3 laps of the course. Men also do 3 laps, women do 2 and juniors do a single lap. Most years the cyclist have the upper hand. If the course is very wet then the runners will have more of a chance.
In the past there has been no charge for racing, although a donation is appreciated by the organisers. I may be there if not racing at Witham.