Queensgate is a castle on the Wall.
In the books
In the A Song of Ice and Fire novels, Queensgate is an abandoned castle on the Wall located between Deep Lake to west and Castle Black to the east. It was originally named Snowgate, but was renamed when Queen Alysanne Targaryen visited the castle on her dragon Silverwing. There was a war between the commanders of Queensgate and the Nightfort six hundred years before the War of the Five Kings.
Stannis Baratheon inspects the ruins of Queensgate and Oakenshield during his stay at the Wall. Lord Commander Jon Snow later gives the castle to the wildling warrior witch Morna White Mask to garrison and settle her people.