From A Wiki of Ice and Fire
Queensgate is an abandoned castle along the Wall. It was formerly manned by the Night's Watch but was abandoned as the Watch shrank. To the west lies Deep Lake and to the east Castle Black.
Queensgate was originally named Snowgate, but was renamed when Queen Alysanne Targaryen visited the castle on her dragon Silverwing. Six hundred years before the War of the Five Kings, the commanders of the Nightfort and Snowgate went to war with each other.
A Storm of Swords
Reports come to Castle Black that wildlings have been climbing near Queensgate.
A Dance with Dragons
Lord Commander Jon Snow gives Queensgate to Morna White Mask to garrison and settle her own people.
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