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.
"The world has an immovable dark red sun in the centre of the sky that produces very little light. The heat is totally unbearable and the aroma of delicious cooking meat is in the air. To look around it appears as though you are surrounded by giant black mountains with no vegetation anywhere. The ground is soft and an oily liquid flows into your footprints. Travelling reveals nothing else."
Any character without some resistance to fire or heat is slowly being cooked. The ground if you haven't guessed it is the cooked meat.
I've wanted this world to be part of a dimensional hopping "chase". I thought maybe to populate this world with giant carnivorous beetles or perhaps this could be a "Nirvana" for deceased or living (but dimension travelling) fire dragons.
Perhaps I've just been grilling a little too much meat or perhaps there are some great ideas out there on how to spruce up the place. Any suggestions?