Erôn-Mystarë; which means "Castle of the Elements" in elvish, was the ancient citadel of the Council of Sorcerë. In the early Third Age, under the direct supervision of the Council, the castle was built directly into the base of Mount Orendren. Mount Orendren was chosen because the ancient Synfari had discovered it to be the magical epicenter of Corwyn.

Desiring its secrets, the castle was besieged by the armies of Alokkair in the year 252 of the Third Age. But he was defeated by an alliance of elves, dwarves, and men at the Battle of Orgorod.

The castle was later conquered in the late Fifth Age by the armies of Sorimmar; who, after capturing the ancient fortress, expanded it for his own use.

Once Sorimmar took control of the Erôn-Mystarë, he renamed it Erôn-Gothmar; The "Castle of Necromancy."