Tim & Patient Zero said it all. People also go sledding, telemarking (using skins 2 go uphill) & snow shoeing is also allowed (rentals available). But certain trails R reserved 4 XC skiers only.
I'm sure you could snowboard down the old downhill runs, but there are no lifts and I've never seen anyone doing it the 20 or so times I've been there.
There is a good backcountry ski community at Prospect that makes turns on the old downhill runs.
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