One part of building the BigDungeon has been wrestling with the whole thing (or at least large chunks of it). Keeping track of one level at a time conceals interactions and just how big a dungeon can be. I worked up a few illustrations to experiment with different ways to work on the BigDungeon.
I worked up a set of colored levels in Adobe illustrator, here they are one over the other in 2-D:
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(click to get the full size image)
Here's the same place in a 3D-ish view:
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(click to get the full size image)
I'm very visual and prone to do "studies" on a subject to see if I'm taking the right approach. The overall advantage of the two maps as presented is pretty minor but it did show me sticking to the same representation for the entire development of a large and complex space like the BigDungeon is not the way to go. Having more then one way to see the place is key.