|First Appearance||Age of Empires II|
|Age Available||Castle Age|
|Base Hit Points||4800|
For the Age of Empires III building, see Castle (Age of Empires III).
- Can heal and Garrison up to 20 units simultaneously.
- Develop the Unique Unit of a civilization.
- Allows the player to develop the Unique Technologies of a civilization and can promote unique units to elite levels once Imperial Age is reached.
- Allows the player to construct a Trebuchet or a Petard.
- Can support up to 20 population.
- Allows the player to gain control over a foreign territory.
- Can fire four arrows within its range without garrison but a fully garrisoned castle can fire up to twenty arrows simultaneously.
Being the building with the most uses and functions, the Castle is one of the most powerful buildings in the game but requires huge amounts of Stone. The best counter for Castles are siege weapons, such as rams, trebuchets, bombard cannons, or Petards. The AI usually builds a relatively high amount of Castles close to the center of the map starting from the Imperial Age at Death matches.
The first castles appeared in Europe in the ninth century as an improvement of the local lord's stronghold. Castles were tactically defensive but strategically offensive. Because they were so difficult to cpature if adequately defended, they provided a secure base from which a mobile force of warriors could extend political control. A local lord installed himself inside with a professional force of fighing men to serve him. Castles spread across Europe in the tenth and eleventh centuries in response to weak central authority and barbarian raids from the north and east. Kings spent the rest of the Middle Ages trying to take back control of castles raised by local lords. The development of dependable mobile heavy artillery in the fifteenth century finally made castles obsolete.
Tactics and Placement Edit
Players should build Castle inside minor fortifications outside their settlement. Surrounding the entire base with walls along with other towers such as a Bombard Tower provides additional protection from Battering Rams and other melee units. If a river separates their base from the enemy's, players should wall up the river's shallows and build a Castle near them. Players should build Castles at major chokepoints, especially if they have researched the Murder Holes upgrade. Players should also garrison a few cavalry units to fend off Battering Ram attacks.
- The Franks can construct cheaper Castles and can use them more effectively to defend their territory.
- The Teutons unique technology Crenellations increases the range of Castles by 3, allowing them to retaliate against Bombard Cannons and regular Cannon Galleons. The Teutons can also research Murder Holes for free upon reaching the Castle Age. This provides them an earlier deterrent to attacks from Cavalry and Battering Rams.
- Byzantine castles have higher hit points than normal castles. A fully upgraded Byzantine castle has a whopping 8131 hit points.
Each architectural group of civilizations has its own unique designs for its castle:
- West European (Top picture) has one tower and a drawbridge.
- Asian (Upper-left of gallery) bear an uncanny resemblence to the main keep of Japan's Osaka Castle.
- Middle-Eastern (Upper-middle of gallery) Muslim-inspired architecture with gold-brown colors (perhaps made of sandstone).
- Central European (Upper-right of gallery) has a blocky design with four tall towers and two shorter ones with a bridge in between.
- Meso-American (Bottom of gallery, leftmost picture of the five castles) resemble tall ziggurats, with a steep staircase leading to the top.
- The entrances of the West European and the Meso-American Castles head to the left, the entrances of the three others to the right.
- The castle is the most expensive building in the military sector.