Map of Pubs in Cambridge

Below is a rather old map of pubs in Cambridge, which I found on the web many years ago. It has since been taken down from its original website, and so I have given it a new home. Unfortunately, I have no idea who its original author may have been, or about their grading system. I used to think that we ought to pay a visit to the Five Bells to find how it achieved such a bad ranking, but unfortunately it's now derelict, so the source of its badness might have to remain forever a mystery.