The Ilumnos Series
Lavarus is the home city of the Fire Dwarves in the Red World. It sits in an enormous open cavern. It actually rests on a huge ledge which overlooks a massive drop into a lake of flowing magma, which gives the city an eerie ambient red glow. A naturally occurring stone bridge that connects to the bottom of the cavern bridges the ledge that the city rests on to the tunnel the dwarves use to get above ground. The ledge is where the daily life of Lavarus happens. Fire Dwarf homes are holes in the far wall of the cavern, caves within a cave. These cave holes are stacked on top of each other with ramps connecting each layer; it is a real dwarven feat of stone work engineering to see. The stone around the main entrance to the temple, palace, and barracks has been impressed so that it appears that a large skull is coming out of the far wall. The open mouth of the skull is the main entrance.
Lavarus is ruled by King Ghok.
Due to the echoey nature of the halls of the underdark, and the existance of the large machine used by King Ghok, I used the soundtrack to the videogame Quake (except for the first track), by Trent Reznor, for it has a wonderful pulsating hum to it at all times.