Luskan, the City of Sails, spans the icy River Mirar, which tumbles from the Spine of the World, races past Mirabar, and then plunges toward the sea. The swift river has cut deep here, and Luskan rests atop two escarpments on either side, with sheer, forty-foot bluffs of gray stone rising above the water. Around the city’s perimeter, thick stone walls with squat towers provide defense. The southern gate, called the Twin Teeth, boasts the most impressive towers, standing twice as tall as the city walls, and bedecked with crenellations and arrow slits enough for numerous defenders, in a show of strength toward the southern approach.