The arrow-head design of the castle's bastion reflected new ideas about defensive fortifications spreading out from Italy in the 16th century.[47] Earlier Henrician castles had used the older European style of semi-circular bastions to avoid presenting any weak spots in the stonework, but an arrow-headed design enabled defenders to provide much more effective supporting fire against an attacking force.[48] Yarmouth was among the first fortifications in Europe, and the first in England, to adopt this design.[3]