Apart from playing in the snow you have Kystendil just down the road which is famous for being an area of outstanding natural beauty as well as having a well preserved traditional town center which feels as if you have stepped back a couple of hundred years in time when you arrive.
Local spa water is said to have huge health and wellness properties so a trip to anyone of the hotels in town offering spa treatments could be another way to spend your time if you finish early on the hill.