Flanking tower

A flanking tower is like a little castle on the side of a bigger castle. It's high up, so people can see far away, and usually has holes in the walls so that soldiers can shoot arrows or other weapons at enemies. The flanking tower helps protect the castle from attacks because the soldiers can see the attackers from far away and shoot at them before they get too close to the castle walls. Think of it like a lookout tower that protects a big castle from bad guys.