From the back cover: The ebon depths of the Underdark have spawned more fables and fears than any other region of Faerûn. In this lightless world, the hazards of its unforgiving wilderness are exceeded only by the perils found within the communities of races such as the aboleths, illithids, duergar, and drow. Explore the labyrinthine tunnels and endless caverns of the Realms Below to encounter denizens and dangers of one of the most intriguing, inhospitable regions in the Forgotten Realms game setting. 60 cities and sites of interest 16 character races 25 new feats Expanded by; Organizations of the Underdark Underdark Dungeons