Parts of a castle 2
A portcullis is a strong gate above an entrance to a castle. It could be lowered to the ground to keep out the enemies. This portcullis is at Bolton Castle.
A drawbridge is a bridge that can be pulled up to stop the enemy from getting into a castle.
Arrow slits let archers shoot arrows at the enemy without being seen. The archers stood inside the walls to shoot.
Look how thick the castle walls are.
From the outside arrow slits could look like straight lines, or like this.
The cross shape let the archers use a crossbow.