An Ancient Ruin                                        -      N      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      -      -

You are standing in the midst of what was once a great work of
architecture.  However, the city's fall from the world above was so
devastating that very few buildings remained intact.  The ravages of time
have further deteriorated the structure, until there is nothing left but
stones and the occasional broken pillar.  
A large stalactite is dislodged from the ceiling, narrowly missing you!