Level 6:  The Lost Level

History:

The Lost Level makes up the sixth level of Undermountain. Until recently, the Lost Level was physically cut off from the rest of Undermountain. But when umber hulks burrowing through the mountain stumbled upon it, they left tunnels in their wake for treasure hunters to follow. The level appears to have originally been a temple complex dedicated to Dumathoin, the Keeper of Secrets under the Mountain.

Physical Makeup:

As it was once a temple, the Lost Level is made up entirely of fine dwarven stonewoork. Floors and Ceilings are crafterd from large blocks of granite and marble, fitted with dwarven prevision. Walls are adorned with frescos and carvings of dwarves in their daily life: mining, crafting, celebrating, and working. Doors are carved from thick pieces of stone and set with elaborate hidden hinges and complex handles with inset mechanical locks.