Yeah, the maps only about half done. I should probably put this into the "Work In Progress" section.

The complex is a natural cave complex that was then modified by an underground dwelling race.

It's actually "level two" of the "dungeon" my part is currently in and the front entrance is the cave on the far right.

There are actually contour lines in the map that tell you what the cave elevations are. I just haven't put the labels in yet.