Westernmost of the nineteen castles the Night's Watch raised along the Wall, Westwatch-by-the-Bridge stands above the Gorge, where the ice ends against the flanks of the mountains. Like most of its sister castles it has stood empty for long years, its garrison withdrawn as the Watch dwindled.
The Bridge of Skulls
Below the castle the Bridge of Skulls spans the Gorge, the one crossing by which wildlings may pass around the Wall's western end without braving the mountains or the sea. Time and again raiders have tried the bridge, and time and again the black brothers have thrown them back; the bones of the fallen gave the crossing its grim name, and the men of the Shadow Tower still watch it in Westwatch's stead.