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. It 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. To the west lies Deep Lake and to the east Castle Black.
A Storm of Swords
Reports came to Castle Black that the wildlings had been spotted near Queensgate.
A Dance with Dragons
Jon Snow gave Queensgate to Morna White Mask to garrison and settle her own people.
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