City wall is one of the two rewards you can choose after you have upgraded a level 2 city to level 3 (the other being Resources). If you choose City Wall, your city will gain a wall visual on the bottom. It gives a passive 400% defence buff to any units inside. Enemy units in your city are not affected. This does not stack with the 150% buff that being in a city gives you.
If you have a defence bonus, a shield will appear around the health.
|Warrior||Rider||Archer||Defender||Swordman||Catapult||Knight||Giant (Super unit)|
|Defense in city without City Wall||3||1.5||1.5||4.5||4.5||0||1.5||6|
|Defense in city with City Wall||8||4||4||12||12||0||4||16|
|Ruins, Population, and City Upgrades|
|Ruins, Super Unit, Battleship, Technology, Explorer, Population Growth, Population, Giant, Park, City Wall, Workshop, Border Growth, Resources|