I came across a stray reference to a drow city underneath Turmish ruled by a queen called Nathglaryst. This city had its links to the surface severed by Harpers between 1146 - 1179 and it sounds like a part of the city is crushed as it severely weakens Nathglaryst's power, although it doesn't say she is killed
A quick search of my archives revealed the name of the city was Undraeth and is located deep beneath the Aphrunn Mountains in Turmish and had tunnels linking it to Oryndoll, Sshamath, Iltkazar and Guallidurth.
The same Undraeth that was attacked by the duergar of Underspires and Duerra herself in -1850 DR.
The same Undraeth and Nathglaryst that sent the kobolds of the tattered cloth tribe to besiege Hlondeth in 527 DR and led to the rise of yuan-ti in Hlondeth.
It looks like this city has had a bit of influence in the lands under and above Turmish and it's interesting because it has a queen. I don't remember any drow settlement having a queen, they always seem to form a tribal organisation involving Houses and other large power groups to keep each other in line.
So this Nathglaryst must be powerful, she is at least 600 years old and must be a super drow to have kept power for so long.
I found a random character that detailed him as a renegade wizard assassin that worshipped Kiaransalee, but that doesn't say what the primary religion of the city was, merely what a renegade worships.
How have we not had more detail about this city.
Anybody know anything more about it than what I have found. A 600 year old drow queen deserved more than a cursory mention.
Polyhedron 140 has a writeup on Undraeth in the Llurth Dreyer article by Eric Boyd, under the "Environs of Llurth Dreyer" section.
If you can't locate it i can quote here relevant parts (like the fact that Nathglaryst is "a sorceress and priestess of Lolth of incredible power" and is "worshiped as an avatar of the Spider Queen"].