Can anyone identify this image of a barely decipherable face, impressed on 
the inside back wall of an old bus shelter?  Could it be Marilyn Monroe?
An old poster?  Take a quick peek at <http://peninsulators.org/Marilyn/>

It looks to me like Marilyn Monroe as she appeared in "Bus Stop."

Here is a poster with a similar wide-eyed, open-mouthed pose:

http://rbenda.bei.t-online.de/pj/pj_090.jpg

It is most certainly Marilyn.  Possible a "flop" (a right to left reversal
of an image) of one of Andy Warhol's silkscreen images of her.  See:

http://www.moma.org/collection/depts/paint_sculpt/images/large/316_62_warhol_marilyn.jpg

Looking Forward, denco-ga - Google Answers Researcher

C'mon, Pink.  Why would anyone paint a picture of Marilyn Monroe from
Bus Stop in a bus stop on Marilyn Monroe Blvd?

The bus stop was salvaged, bought from the county by my mom.  She was a
M.M. fan and added the Blvd sign.  The image was noticed later, so if it
*is* M.M., it's a coincidence.  Neither of those two Marilyn's seems
like an exact match, but that beauty spot sure looks to be in the right
place.

Yes, it's definitely MM, but from a photo taken more towards the end
of her life. This image was once used on the cover of a book I used to
have. Can't remember the title at the moment to be able to search for
it.

Looks like a slightly distorted version of this cover:
http://www.amazon.com/exec/obidos/tg/detail/-/3823854674/qid=1088557589/sr=5-1/ref=cm_lm_asin/104-1175791-4538337?v=glance&s=books

...reversed.

I've been looking through image searches and book covers, but all the M.M.
images I see, she's usually got the half-open bedroom eyes, sleepy/sultry
looking.  In the image from the bus shelter, the eyes are surprised/wide-open,
quite a difference.  If the image *was* from a book cover, it must have also
been used on a poster or advertising of some sort?  Presumably the image was
transferred from a poster to the back wall (this is Washington; it's pretty
damp up there).