A Tiny Islet                                           -      -      - 
(-------------------------------------------------)     W <---(M)---> -
                                                        -      S      -

You are standing atop a small pile of rocks in the corner of a massive
subterranean cavern of some sort.  A huge underground lake surrounds the bit
of dry land you occupy, and it is impossible to see the other edge of the
water through the darkness.  The massive stone walls of the cavern rise up
to the east and the north.