3 adjectives to describe postern

He had now come to a narrow passageway leading to the last of the inner posterns which pierced the walls.

They opened a little postern and let in the few who carried her things, and who had been shut out with the crowd.

They were, therefore, compelled to make use of the regular passages to the outer posterns and these latter being located at a considerable distance from the prisoner's avenue of escape, he was certain, at the pace he was maintaining, to gain at least a half-hour's start over his pursuers.

3 adjectives to describe  postern