In the medieval fortification, the type of tower that is open, or only lightly constructed, at the rear. It can be semicircular or quadrilateral. On rear side, a wooden railing on individual floors stopped people or objects from falling off. Sometimes the open side was sealed with wooden planking or weaker timber framed walls. The half towers were armed with equipment typical of the defensive wall. Over time the half towers were rebuilt to form of closed towers.
