A little way up the narrow valley, before they reach the woods, the PCs notice the squat, tumbledown buildings by the riverside. They are hardly big enough for a human to stand in, and the complex cogs and shafts that occupy the central cavity of one of the buildings are perplexing. What were these buildings? And how safe are they to explore?
Alternatively a desolate place is the perfect setting for a derelict chapel or croft. There needn't be any actual physical encounter involved, but it adds atmosphere to a place to see its dead history. For instance, in the Outer Hebrides there are whole deserted villages which were razed to the ground by the English during the Clearances. Such stories give a setting authenticity and character.
You meet a large number of villagers, walking and weeping beside the coffin of an old bearded man (or adapt to your funeral customs). If asked properly, you learn about an old wizard, a wise man that long helped the tiny village to grow and prosper. Even after death he shows his favour: he gave most of his possesions to the poorer members of the community. All the villagers show him now respect this way. Why do you ask, are you adventurers? (As a last wish, he left a tiny case for the first group of adventurers that crosses the village).