Kizan Line

The Kizan Line, a spoke of the Kibar-Kûn, is a railroad originating in Bolnalmak, a prominent rail hub city. From this city, the line descends 500 feet to the Underdark city of Dabul-Gind, then continues westward to the underground portion of Rumaktharga. Except for a few locations, the 160-mile section between Dabul-Gind and Rumaktharga traverses the Brother Tunnels.

The rail line typically runs 200 to 300 feet underground. This depth was chosen to maximize the efficiency of the exhaust chimneys for the train smoke and, more crucially, to reduce the cost of boring out the tunnels, as preferred by the Phorngoad Rail's board of directors. As on the surface, travel along the rail is sluggish, a precaution against Underdark perils such as cave-ins, train-robbing bandits, and opportunistic scavengers who may plunder the tracks for iron.