The Drow Tunnels are populated by evil dark elves which are really dangerous. But there are also some mystical creatures which are waiting for their next victims...
The Drow Tunnels which you can access from different places all around the Nalwor area, are build from Dark Elves which builded up a massive amount of underground corridors some time ago.
After some experiences with normal Elves, a new kind of Elves, a dark and bad one has been created. That kind is living in these tunnels now, waiting for young heroes and new victims for their rage against human beings. But these Dark Elves are not the creatures which are living there, there are also other creatures like a huge giant spider which is waiting for human flesh. Also some matronmothers with their poisoness arms are waiting.
There is also a npc in Nalwor called Maerion who has a huge task for you and a nice quest reward after that... You should visit him when you are ready for an awesome adventure down in the Drow Tunnels!