The whole story of Cephalus and Procris is about hunting, so it's no surprise that most of the goings-on happen in the woods and hills, where Cephalus likes to do his hunting. Nothing sneaky happening here—just an appropriate setting for the story.
We can't forget Eos's pad, though. Though the story doesn't go into a lot detail about it, some sources tell us that she lives at the edge of the world on the shores of Oceanus. Pretty stark contrast from the woods, right?