Szith Morcane was an underground city of drow north of Silverstone. It was one of many enclaves magically shifted out of Doth'Mordun in 2930 as part of Kiaransalee's attempt at opening their prison. The city is built into the side of a cliff, which is covered by an enormous spiderweb that is used to get around the city.
After the city was shifted out of their prison, a squadron of drow warriors emerged to the surface to attack Silverstone. They were defeated, however, and the Brighstone Heroes were sent in to clear out whatever drow were left in the city. It was within Szith Morcane's temple that they located a portal into Doth'Mordun, allowing them to foil Kiaransalee's plot. Afterwards, the passage between Szith Morcane and the surface was magically sealed.