41. They were constructed about the central part of the community with four main gates and three postern gates. 42. Today, the secret passage's postern is closed off, but the path is still there. 43. The codename for the main operations to take Lae was "'Operation Postern " '. 44. In addition, posterns ( side gates ) were provided, for example at Gray's Close. 45. A small postern ( auxiliary ) gate was located immediately north of the second tower on the eastern side. 46. There remains a postern , some ramparts, and Our Lady of the Castle which was built in 1148. 47. In 1829, the bridge was rebuilt, and the Postern and a short section of wall were demolished. 48. Frequently, small, hidden sally ports or posterns enabled direct combat with an enemy in the moat area. 49. The three parts of the complex ( east, west and south ) all had posterns with battery artillery. 50. Additionally there were pedestrian-only gates such as Tower Gate and the postern gate at the Tower of London.
