Hmm, the character I've just created is a Pathfinder and has a compass...alas that only amounts to +2 on survival checks.

Great idea and it's looking great already. As much as I love the look of your natural caverns it seems that someone that went to the trouble to build all of this would have wanted nicely worked walls too...unless specifically didn't, in which case it might make good backstory. What about teleports? It needs teleports too!

I can see something like this on Mechanus. Except there'd be a very precise order to its functioning (and those rough walls would never do, not at all). Oh, and, there'd be many, many of these rotating thingies all next to each other and interconnected. Populated by Modrons who'd be very mad about intruders (or Formians if you're a 3E Planescaper...in which case maybe rough walls are okay, as long as the corridors are orderly). Loves me some Lawful wickedness.
M