The Dericost were ancient occupants of Auberean, some of whom occupied Ireth Lassel and its constellations of neighboring islands. Known Dericostian locations are the frigid northern plateau of Gelid in the north of Dericost, the heart of the Kingdom, Dericost royal Province, with the seat of the throne in Vasmora, the town of Daralet in the Dericost marshes, the Valley of Tresimaen with the town of Cannthalo in the northeast and the peak of Zemal in the southwest, the town of Antaoc in the lowlands of the Ashatiri region, whose inhabitants quarried the granite of Nehane Mountain, and the Fortress of Hirschi.