Londoners and Northerners!

I thought I'd draw your attention to this excellent blog: 'Route 79 - Reflections on a Bus Journey Home'! I was particularly amused by the following snippet:
"In London - the term 'up North' means anywhere north of a London town called Watford - although I have to say that this term is used as a deliberate form of ignorance designed to upset 'Northerners' who go about life believing that Londoners are completely self-centred and think that the universe revolves around London."
I also grew up on the expression that anything north of the 'Watford Gap' was considered 'up north' (at least to us southerners!) - the Watford Gap being the motorway services on the M1. There is a village called Watford very near to Watford Gap, so there are a variety of 'Watfords' to consider as the gateway to the north (unless you're a northerner in which case, I imagine, none of them would count)!