Note that when an English person says the north, they expect everyone to know they are talking specifically about the north of England, not the north of the UK even if everyone else is talking about the UK.
Similarly, Americans expect people to be aware that California is not "the South", despite being on the southern border, and that the Midwest is actually in the eastern half of the country.
Basically the names of geographical regions don't always make sense.
I think the original phrase was "North of the Watford Gap", but people often mis-abbreviate to "North of Watford". The Watford Gap is not the same place as Watford. It's about 75 miles north of London. Watford is within London's motorway ring road (The M25), and on the underground map. Its only about 17 miles away from the centre.
Did you know that most people outside the US do not intuitively understand the arbitrary US delineations for North, South, West, Midwest? And yet, "they expect everyone to know they are talking specifically about..."
You have to remember what public transit is like in NA. What in Europe is unacceptable, late frequently, and problematic, is probably the best public transit someone from NA has ever been on, except maybe the NYC subway. It's a really, really low bar. NJTransit is considered one of the best in the US (and it is, unfortunately), and it's worse than anything I saw in Europe when I visited.