The fictional world in which the A Song of Ice and Fire novels by George R. R. Martin take place is divided into several continents. Most of the story takes place on the continent Westeros, which consists of the Seven Kingdoms (the North, the Iron Islands, Mountain and Vale, the Rock, the Stormlands, the Reach, Dorne) and an unmapped area to the north, separated by a massive wall of ice and old magic. The vast continent of Essos lies to the east of Westeros, across the Narrow Sea. The closest foreign nations to Westeros are the Free Cities, a collection of independent city-states along the western edge of this eastern continent. The lands along the southern coastline of the eastern continent, collectively called the Lands of the Summer Sea, include Slavers Bay and the ruins of Valyria, the former home of Westeros' Targaryen kings. To the south of Essos lies the continent of Sothoryos and Ulthos, which in the narrative are largely unexplored.