The third walled enclosure, the largest that exists at the fortified settlement of A Saceda, is the only one that possesses a postern, a name given to the secondary doors of a fortified space, created for the exclusive access of people. It was discovered in the 1988 archaeological campaign, and since then no consolidation or restoration work has been carried out. The postern of A Cidá da Saceda is an oblique cut in the wall that is located in a hidden part of the wall, therefore, separated from the preferred main access to the site. This allowed the inhabitants of the settlement to come and go without being seen.