Golarion contains eight continents amid its immense seas. The largest of these is Casmaron, which spans much of the world's northern hemisphere. On its western edge, bordered by the World's Edge Mountains, Casmaron expands into a large peninsular continent called Avistan which plays host to a number of civilizations built upon the ruins of great past empires, such as that of the Thassilonians. The smallest continent on Golarion is Sarusan, which lies amid the least traveled portions of the sea. An immense frozen desert spans the northern pole of the planet, called the Crown of the World.