An opening in the wall of a fortress, through which missiles were discharged upon an enemy
Additional defenses in front of a gatehouse whose purpose was to restrict access to the main gate Often contained drawbridges and parapets from which defenders could shoot down into the roadway
The gateway or outworks defending the drawbridge; An outwork or forward extension of a castle gateway
A tower or advanced work defending the entrance to a castle or city, as at a gate or bridge
A defensive structure located at the gate of a city or castle Found close to (or sometimes attached to) the exterior wall , a barbican is usually heavily fortified for the use of guards