Serolen, meaning Duskwood in Crepuscular, is the name given by the Drow to the large forest in the northern part of the Kingdom of the Dead, between Lake Netzach and the Chalice. It is also the temporary name of the Drow settlement in that forest, although Catherine has expressed strong opinion on the inconvenience of using the same name for a city and its surrounding region and expects this state of affairs to change.
The entire forest is covered in perpetual dusk due to the Gloom, allowing the Drow to use their Night powers and not suffer from the coming of dawn. The city of Serolen is being constructed out of remnants of the old Everdark, brought up to the surface and built into the woods rather than replacing it, and trees shaped through the use of Night into support pillars, stairs, roads, pieces of art and whatever else is needed. Crop mushrooms brought up from the deeps have spread throughout the forest, and the Drow have redirected streams and brought up water from underground reservoirs to form an artificial lake in its heart. On its shore stands the great temple of Holy Tvarigu, once the seat of the Twilight Sages and now home to entire flocks of Sve Noc's crows.