The Rules
From Tolkien Gateway
The Rules were essential laws that the Shire-hobbits kept of their own free will, recognising their justness and antiquity. They attributed them to the old King of Arthedain.[1]
During the time of the Kings, the Hobbits were obliged to acknowledge their lordship, to speed their messengers, and to maintain the Shire's bridges and roads.[2] Possibly their obligations included allowing the King to visit the land three times a year for hunting, as the woods and moorlands of the Shire had been a royal park.[3]