A Narrow Entryway                                      -      -      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      S      -

Upon entering through a fairly narrow doorway, you find yourself standing
in a mostly empty circular room.  The wood floor is dust and dirt covered. 
The walls are made of huge field stones that are showing its age.  The
wooden floor creaks eerily beneath your feet causing you to look down. 
There is a trap door in the middle of the floor, with a large, thick ring
set into it for a handle.  The hinges appear badly rusted but intact.  What
could possibly be down here?