exercise in building a megadungeon as an exploration of setting as space, inspired by the appearance of the Balrog in the Peter Jackson LOTR flick...
...and this reminded me of the Middle-Earth Role Playing module Moria: the Dwarven City.
Now, this thing is huge. In addition to the seven levels of mines, it has the seven deeps that the dwarves delved into before they 'delved too deeply'. Due to scale, there aren't maps of the entire place. There are several maps of the various levels, and several cross-sectional maps showing how all these 'dungeon levels' are connected. One of those maps is, of course the cross-section to the right featuring the Endless Stair and Durin's Chimney.
Please note all those little bridges that connect various gaps in Durin's Chimney! Also, those little domed areas are other areas that are detailed in the module.
Last but not least, it may seem to you that the mine seems somewhat narrow. That's because we're looking at it (1) in comparison to the length of the Endless Stair; and (2) those corridors actually do go on quite a bit more (there are little symbols that say the corridors are 'cut' to fit the map.
Another map that I wasn't really sure how to use was the map of the Balrog's Lair. I mean, when where the players supposed to encounter this? Of course, if you run a game anytime after ol' flamehead's altercation with a certain grey wizard it would be free of any infernal entanglements -- or would it be?
Now, because of the scale adventuring in this place requires planning, rationing of all supplies, being fleet of foot (we have to walk how far to get to the next room?), and probably a continual light spell or two.
Actually, now that I think about it, I'd probably have the cleric in the party cast ten continual light spells on coins. Each party member gets one, and the extras get thrown ahead and retrieved as people move forward, or left behind to keep an eye on possible entrances and exits, etc.
Water sources become a problem here, especially if you're keeping track of sustenance for your player's characters. I mean, how clean is the water when you can find it? The location of water pools and rivers and streams are of prime consideration so that you can keep refilling those waterskins.
Again, the cleric spells become key in making water (and food) available and consumable.
In any case, the dwarves (and the ancients) certainly built big! And if I were going to go into this megadungeon, I'd certainly be a bit cowed by the scale of the vaulted ceilings, the chambers and corridors, and so on.
It's very different from the take that Mystara's Dwarves of Rockhome Gazetteer, but that was pretty big too. Maybe I'll tackle that in another post.