Is a mystery to me as well, but 100 years ago this might have been some sort of well known resort.
But look at the train "station" in the second photo. It looks more like a bus stop? There is also an interesting structure up on the ridge at about 1 o'clock in the first photo . Looks a little like a sculpture of a man with a bow and arrow. I seriously doubt that's what t is
I looked over the area with Google Earth. There is a whole lot of nothing in the immediate vicinity. The site of the hotel is apparently under I-81 right of way. There are a bunch of two tracks winding up into "Blue Mountain".
There is a large poultry farm just east of the old site on Fort Swatara Road and a National Guard base and an adjacent Army base just east of that.
Apparently the pass was considered strategically important even in pre revolutionary times and a fort was established to protect it, hence Fort Swatara. Any dates on the photographs?