Note 25 — Chapter V · The Castle, the Walls and Mediæval Fortifications
Reading edition
The original entrance to these passages cannot be determined now as the principal tower which might have been the last place of refuge and the extremest point of defence no longer exists. To-day the entrance is to be found in the Tower at the most westerly corner of the Castle grounds. We shall come to the subject of the subterranean passages in the next chapter.