Undermountain

Undermountain is a huge dungeon complex created by the mad wizard Halaster Blackcloak and located under the city of Waterdeep. It continually changes according to Halaster's strange whims. He summons monsters into his dungeon from their homes, trapping them there and creates traps to test adventurers venturing down into the dungeon, looking for fame and fortune.

History

 * -1288 DR: King Melair I discovers mithral ore underneath Mount Waterdeep and creates a home for his Melairkyn, beginning to carve out caverns and tunnels
 * -750DR: Netherese wizards occupy the third level of Undermountain and seal it off against the Melairkyn. Some scholars call this the Sargauth Enclave
 * -677 DR: The drow begin to occupy more and more of the area held by the Melairkyn
 * 34 DR: In a large shift of territory following a massive drow invasion, the Melairkyn lose a lot of their territory
 * 168 DR: Halaster Blackcloak claims the Underhalls of the ousted Melairkyn for himself.
 * 171 DR: Halaster begins Halaster's Hunts which wipe out large numbers of the drow and duergar from Undermountain and continue until 308 DR. Many drow and duergar are forced out during this time.
 * 268 DR: The mithral is now completely depleted
 * 284 DR: The duergar leave Undermountain, having no reason to stay without the mithral resource
 * 309 DR: Halaster becomes ruler of the Underhalls
 * 493 DR: The drow leave Undermountain entirely