An undecorated postern gate also was constructed through the north wall.
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This section of wall has six openings at the base, one of which served as a postern gate.
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Postern gates were built into towers or near them to allow sorties.
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At the rear of the fortress, another barbican guarded the postern entrance from the River Conwy.
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Amador opened the postern in the north wall, allowing Mexican soldiers to pour into the complex.
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Near Wakefield Tower was a postern gate which allowed private access to the king's apartments.
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During this time, the town was fortified with defensive walls, three main gates and a postern.
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Probably around the 1250s a postern was added to the north wall.
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Immediately north of the kitchen was a postern tower.
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More examples
A small gate in the rear of a fort or castle
A postern is a secondary door or gate, particularly in a fortification such as a city wall or castle curtain wall. Posterns were often located in a concealed location, allowing the occupants to come and go inconspicuously. ...
A back-gate, backdoor, side entrance, or other gateway distinct from the main entrance; By extension, a separate or hidden way in or out of a place, situation etc; Situated at the rear; posterior
A passage leading from the interior of a fortification to the ditch.
Any access or entrance other than the main one, as a private gateway or back door; refers to the "people sized" door (also called "pocket door") in a large portal or HATCH cover. Compare EMBRASURE.
Small gateway in a castle from which the besieged could sally forth.
A tunnel serving as a means of access to the ditch and outworks. 1704.
Minor gate or door in a late Roman town- or fortwall
A small door or gate away from the castle's main entrance that was often hidden to allow castle defenders to enter or exit without detection; a castle entrance located in the back of the castle