The Sellen Hills region of Numeria is a harsh hill country east of the Sellen River. The land barely supports life and is dotted with technological ruins. Giants, orcs, and other monstrous tribes fight with the many nomadic Kellid tribes for territory. Further east of the barren countryside, the area is home to spine dragons, wendigos, and other monsters. To the south, the Sellen Hills give away to the Branthlend Foothills which become the Branthlend Mountains in the River Kingdoms. The river traffic is constant up and down the Sellen River from Hajoth Hakados to the large city of Chesed. Streams of soldiers and crusaders are heading north. The Technic League has little power in the region but its presence can still be felt.
Paizo published a major chapter considering the Sellen Hills in Numeria, Land of Fallen Stars.