Each Minor settlement has an auxillary unit protecting it, a hospital of some sorts, homes, and stables. Each Major settlement is protected by a auxillary unit or Legion/Legionnaire cohort. It has a hospital, school, stables, and for the capital, a government building.
The settlements are literally built INTO the wall, protecting it from attacks along both sides, and also allowing for troops to patrol the walls close enough to their homes and also knowing their homes are protected. A mailing system is set up, with riders riding usually small, but extremely fast horses inside the wall. The fields are cleared for around 1 to 6 miles in each direction along settlements, so that the sentinels have a good view of each side, and so archers can accurately hit targets. Enemy forces will have to conduct open-field attacks instead of sneaking up to the settlement's walls.
