Select all that apply. Which statements about a concentric castle are correct?
It had two or more rings of walls, one enclosed within another✓Correct answer
Attackers who captured the outer wall still faced a higher wall inside it✓Correct answer
It was the earliest form of castle built anywhere in medieval Europe
It was a later development than the earth-and-timber castle✓Correct answer
It consisted of a single square tower with no surrounding wall
Explanation
Rings of walls set one inside the other meant that a breach only brought attackers into ground overlooked from a taller line behind, so the defence could be surrendered in stages instead of all at once. The claim that this was the earliest form fails because such a layout needed money, planning and years of construction, and it appears well after the first quickly raised earthworks.