Yep, it sure is. I just looked at it on Google Maps, on the "earth" view, and it is literally in a hole surrounded by mountains. Even if there was wind, it would be coming from different directions every 10 seconds.
I hung under a 15' traditional box in a seat harness about 90' up in the early 60's. I could see all of Lakes Elizabeth and Marie in Twin Lakes, Wisconsin from up there. Aluminum angle rods, braided steel cable rigging and "flying line" and handmade leather shoulder/seat harness, similar to a parachute harness.