David Howery
Hero
while you can make an argument for 'logical' dungeon layouts... none of that applies to natural caverns. Maps of real cave systems like Carlsbad abound online, and they are way chaotic. Adapting this to a FRPG Underdark is pretty neat. You can assume that the natural cave tunnels have been augmented by Underdark races digging their own accesses and rounding out irregular caves. Real cave systems have some features that would be sure to be frustrating to PCs.... tunnels that increase/decrease in height/width as you go along, others that just dead end in blank stone... or water, some that end in cliff walls that you have to scale to continue on, etc. The old 1E DSG had a lot of stuff on this...