These buildings is any building that helps defend your city, that isn't a unit, but a building.
- Walls - Used to block off/slow down [ground unit] enemies from entering cities. Best used when defended. Can be upgraded (for health).
- Sentry Towers - Buildings used in every religion that shoots arrows. Can be upgraded.
- Egyptian Fortress/Greek Siege Works - Shoots powerful arrows like a Sentry Tower. Shooting ability cannot be upgraded.