Did I just miss that?@David_Vi
"Do I need to book? No booking is neccessary, simply turn up and enjoy on the day. The same for the competition, sign up is on the morning of the event. A small fee for the competition usually goes to charity.
Is there accomodation at the venue? Not at the venue, but there are many places nearby, many regulars book an airbnb or the Travelodge is a good place to stay too. https://www.travelodge.co.uk/hotels/20/Cambridge-Swavesey-hotel"