According to elven history, Ashemhorn was the natural border between the elves of southern Turgon and the greenscale of the north. Before the Phael-Tetramord War, it was verdant, pristine valley surrounded with beautiful snow-capped peaks encasing dense evergreen forests, and an open valley with a large and placid lake. Majestic waterfalls spilled into crystalline pools, and then flowed towards the great lake of Vardamir. The streams and rivers that flowed through the valley went past old and overgrown ruins of an unknown civilization. The bricks of old streets were noticeable in some areas, exposed by erosion or marauding beasts. Many ancient decorative arches spanned the streams and one massive arch spanned 500 yards across the main river of Cirathrin. The elves recorded more than 1,000 monuments and statues in the valley. The greatest structures in the valley were six spires cut into the shape of eagle heads - the Turgon Aeries.
In the Year 75, the Turgon Aeries underwent a dark change. Their faces broke off revealing leering demoniac heads spewing gouts of fire and releasing plumes of smoke.
Today, the valley is a steamy, desolate area, with billowing clouds of gas and vapor, and holds innumerable stagnant pools. The most dreaded creatures of the valley are demoniac elephant-sized hounds called mivilorns.