As you fight/sneak your way into the mountain you find yourself in 9 X 4 foot unnatural tunnels. The walls are smooth with occasional magically enhanced wooden supports. Your footsteps tend to echo off the walls. A feeling of foreboding surrounds you-- and those unable to handle close quarters find the negative effects heightened.

(Every adventuring party that enters a new way will have a separate map created by them. You will be given decisions as you hit intersections, doors, rooms, caverns, etc. Should you make your way to the next stage a GM will let you know)