Crown of the World
A sprawling arctic desert called the Crown of the World squats upon the brow of Golarion, grasping with icy mountain claws the northern reaches of Avistan, Casmaron, and Tian Xia. An unforgiving realm home to ice dragons, frost giants, remorhazes, arctic worms, and worse, the Crown of the World nonetheless sees a great deal of traffic, as its frozen trails offer a reliable crossing between continents despite the considerable natural dangers. Most travelers stick to the well-worn Path of Aganhei, named for the Tien explorer who first charted it several thousand years ago. The treacherous route leads from Hongal in the northern reaches of Tian Xia through a winding series of ice ravines and open arctic wasteland before finally reaching the Icestair in the Realm of the Mammoth Lords, where a mighty glacier forms a natural descent to the hard earth of Avistan.
Encased deep in the ice, at the very top of the planet not far from the Path of Aganhei, are the ruins of an ancient humanoid civilization, its name and legends long lost to history. The ruins predate Thassilon, predate Azlant, predate even the coming of the aboleths to Golarion, and their existence and origin remain among the world’s most intriguing mysteries.
Sources: Pathfinder Chronicles Campaign Guide