Access to the ramparts is through a small door that is bolted from the inside. This is the only way out onto the roof.
The door is 3ft in width and 5ft in height and has 4 windows in it.
Between the 13th and 17th century it would have been a Yett that was in place but as threats diminished the door would have become less secure and windows added to allow additional light inside the attic.
A Yett is a strong wooden door with latticed iron bars and a small viewing hole also covered in the lattice to observe who was tring to get entry.