On the Cavern Floor                                    -      N      - 
(-------------------------------------------------)     W <---(M)---> E
                                                        -      S      -

As you traverse the cavern floor, a green glow illuminates your path.  To
your northeast, a skeletal bridge rises above the mists of an underground
river like some prehistoric beast from your nightmares.  The sounds of the
river ring in your ears and the sounds of water dripping from the ceiling
threaten to drive you mad.  
A small black salamander crawls around the cavern in a search for food.