I believe it is Gate's Park that was built by the Forest Service in the early 1960's. It was promptly closed in the mid 1960's by the Forest Service who built it. It was built to give access to the Bob Marshall Wilderness area, but it didn't fit within the wilderness plan, so was closed. Everything hauled in to build it, had to be hauled out. We flew a DC3 in to haul out a tractor used to build the strip, which had been cut up to get in the plane. We used a log tripod/lift to get the cut up parts loaded. We could have used Courierguy (Tom) and his lifting expertise, we dropped the biggest and heaviest part on a helpers foot. There was a caretaker(real old timer and character) that lived there most of the year who would harvest an elk and use every part. I was not smart enough to carry a camera and document a wilderness lifestyle that would disappear from the lower 48 in just a few years. It is a beautiful airstrip and still very useable, which explains the X's placed on it.
The difference between this strip and some of the wilderness strips in Idaho, Gates Park was built in an existing wilderness area and many of the wilderness strips in Idaho were grandfathered in when new wilderness areas were established.