Lake Hatosvir is in the northern reaches of Huzar-Arân. It is fed by the heated waters of the river Galsour which begin cooling a mile out from it at Belfdagny and then as it merges with the lake. Hatosvir is a relatively shallow lake with some areas at most two hundred feet deep. Outside of dry spells, the waters of this lake are always overflowing into natural channels diving downward into the Underdark. These ducts, and in some cases passages, serve as links between Huzar-Arân and the sector below it. There are hundreds of these channels some so small to be barely noticeable and others large enough to serve as roads for Underdark travelers. Galsour's overflowing waters go down these channels back to where it all started in super-heated regions below, where the whole process begins anew. The structure behind this movement of water to Galsour from an even deeper Underdark region is called the Kossuth Aqueduct. If not for this god-made marvel both the river and the lake would not exist.