The Kern River was a river running through the easternmost border of the Midlands. It was one of the three big rivers beside the Drun River and the Callisidrin River.
It originated in the north of Aydindril and continued south toward the mountains. It was one of the big rivers of the Midlands. Partially along its course ran the Boundary between the Midlands and D'Hara. Before flowing into the ocean near Tanimura the Kern River also flowed along the boundary between the New and Old Worlds.