Drow outpost in the Underdark
The drow outpost is located high in a cavern, built 100 feet above the rocky floor. The outpost consists of a series of small caves in the cavern walls and four "hanging towers"-hollowed-out stalactites connected by walkways, stairs, and rope bridges. The towers are concealed by the thick webs of giant spiders stretched below them, so that only the lowermost parts of the stalactites are visible from the cavern floor.
With the small amount of dim light used in the outpost shielded from the cavern floor below, one might walk the entire length of the cleft without becoming aware of the outpost overhead, hidden in the darkness above the range of torches and lanterns. The giant spiders also serve as guards, dropping down on their web strands to prey upon creatures that find their way into the cavern. Similarly, drow warriors can drop to the cave floor on lines of spider silk to ambush enemies.
Three caves and two hanging towers surrounding a platform make up the main part of the outpost for the drow warriors. The largest of the hanging towers is reserved for the priestesses and the shrine of Lolth, while the other is a guard tower opposite the cave used to hold slaves. North of the slave pen is the den of the outpost's quaggoth servants. Watch posts lie at either end of the outpost, near the northern and southern entrances to the cavern.