Originally there was only four entrances (or gates) into the walled city i.e. Bishop’s Gate, Shipquay Gate , Ferryquay Gate and Butcher’s Gate — arranged in a cross apttern with the Diamond at its centre. Drawbridges and portcullises were used to protect some of the Gates when under attack. Later were added New Gate (1789), Castle Gate (1803) and Magazine Gate (1865). The original gates were themselves re-built in the 18th and 19th centuries.