A clue in the crossword

Took a route to Picadilly Station in Manchester which includes part of my normal walk to university. A passage which is normally covered in graffiti has been repainted but the doodles are slowly and surely coming back again. A couple of the more interesting examples here.

Incidentally, I photographed this passage previously and pictures are on my other blog sometime last year: http://fwilsonphotography.blogspot.com/2010/11/railway-arch-graffiti.html