Brent P. Newhall's Musaeum of Fantastic Wonders

The Labyrinth, originally one giant spell circle, never completed

The Darksea, lakes that connect to each other, hundreds of miles across when combined.

Underhold, the free city of the Underdark and also on the shores of the Darksea.

Menzoberranzan, the capital city of the drow

Caer Storga, a fortified outpost that has traded hands many times but was most recently in the hands of the duergar

The lair of Coravorax the Destroyer, a surprisingly young white dragon