The Sür

The Sür; meaning the "foul lake," is a poisonous body of water in southern Morgoth.

Originally, the Drothë built a castle on a small island in the center of the lake for magical experiments. The occupants of the castle used the surrounding lake for testing magical brews which resulted in the permanent pollution of its waters. The lake can now be traversed only by boats with metal hulls, because of the terrible corrosive effects of the acidic waters. In the center of this lake is an island that is home to Erôn-Mored, the citadel of the Zûl.