The Postern Tower.
The Postern Tower provided defence to the rear of the Castle and, as such, bears many similarities to the Gatehouse, although, generally on a smaller scale.
The tower would have been entered through a door at the end of the screens passage and on entering the passage look for more meurtrieres in the ceiling. The outer end of the passage was protected by the castle's final portcullis and further splayed windows give a panoramic view of the north, a newel staircase provides access to the other floors.
The first floor room was the portcullis chamber and would have housed the mechanism for raising and lowering the great iron gate. In addition this bare, working room, like the one above it, contained a fireplace and a guarderobe.
The curtain wall was accessible from the upper chamber of the Postern Tower and the staircase also continues to the roof.
Although not crenellated, machicolations were built into the floor to offer close to the wall defence agains attackers. The stone shoulders that support the over-hanging roof are called corbels and the machicolations can be seen between them. It is possible that the tower was crenellated, but these defences are no longer present.
At the very rear of the castle and the Postern Tower is a stone bridge abutment with high walls (photo). This, of course, provided the rear access to the castle, but nonetheless required heavy defences. Now solid, the bridge abutment provides us with a great view of the moat and surrounding landscape, but in 1970, excavations revealed that it would have been hollow. There would probably have been a drawbridge crossing the hollw and further marks in the walls suggest a further outer gate that swung back against the walls of the bridge.
There is interesting decoration on the outer wall of the Postern Tower as well. Three stone shields are carved in relief on the wall and, although the two outer shields are blank, the central one shows the coat of arms of Sir Robert Knollys. The arms are set at an angle and there is the helmet with the ram's head above it.