I discovered a part of the fort that I think I really wasn't supposed to be able to access. Taking a dark passageway back down from the upper level, I eventually was met with a locked door. I guess they forgot to lock the upper entrance to this area. The bright light you can see in the background is one of three openings that look upon the pedestrian street outside the fort (I'm at the middle level here, so above ground). I sat down in this chamber for a bit of a snack and some people watching.