I started at age 13 in 1967 at a place called Blue Knob, PA. This is what it looked like back then, slopes go out of view to left.
BK is an "upside down" ski area with lodge, parking and service buildings at the summit, elev ~3000'. It had been a cold war USAF Air Defense Radar Station until the early 1960s when that closed and they started the ski area. A lot of the buildings in above picture from mid-1960s are leftovers from the USAF station. The ski area re-purposed many of them for a few years before they replaced them or tore them down. BK is a pretty cold and rugged place in winter by mid-Atlantic standards because of the exposed summit location. My family used to joke that the "Blue" in Blue Knob stood for the color of the ice on the beginner trails that was made from the crummy fire hose-like equipment that passed for a snowmaking system in the 1960s.
Here's another aerial view, I would guess from about 1980, summit is to the left: