I'm with Toady and James on this. I spent twenty years cycling around central London, and cycling in Hertford is diabolical in comparison. The other day, on a short ride from Tescos to Bengeo I had no fewer than three drivers attempting to flatten me. One of them pulled out of a T-junction right into me, and as far as I could tell from the stare the driver gave me, it was done entirely on purpose.
I am intrigued as to which footways/pavements the offending cyclists are riding on. I've not noticed any endemic problem here. Most of Hertford's pavements can hardly fit a pedestrian, let alone a bicycle, and I have no idea how anyone would manage to ride on them given that they are blocked with pushchairs, pedestrians and loiterers. There are however a few shared-use paths (e.g. past McMullens towards Folly Island) and some bits of unfortunate planning that leave cyclists baffled - such as the "Toucan" (i.e. shared use) crossing over Gascoyne Way towards the Castle, which you can't reach on a bicycle without mounting a very narrow stretch of pavement.