The 'Right to Ramble' or 'Crow' is on the following link; and I expect people try to stick to most of the rules.
Shutting gates, not damaging walls or hedges, dogs chasing livestock, or leaving litter should be commonsense.
The Wiltshire landscape you wander around Chance is pretty open anyway, and if you've got a bike you can always getaway from charging bullocks ;)

http://www.ramblers.org.uk/freedom/restriction/