Moondeep Sea

The Moondeep Sea was a subterranean lake, approximately wide, found in the Underdark beneath the Galena Mountains and the cold plains of Vaasa.

Geography
The Moondeep Sea was located in the Upperdark. The cavern which contained it was known as the Vault of Gnashing Teeth, so named for the countless animated skulls stuck to the cavern's ceiling. The water of the lake was fed from the Great Glacier.

The lake was surrounded by a confusing network of tunnels and caverns known as the "Lost Ways," remnants of the ancient Dwarf kingdom of Sarphil. These passages wound beneath the lake and deeper into the Underdark.

The city of V'elddrinnsshar‎ lay on a mile-wide island dominated by a plateau in the middle of the lake.

Flora and Fauna
The Moondeep Sea was known for its giant water spiders.