[Fnoord]

I'm from near that region. It was called N2 (not A2) in Maastricht for a long time, while the rest of the road (from Eijsden near Belgium to Amsterdam) was mostly [1] called A2 though some parts were called N2. Why? Because you were only allowed 80 km per hour there. Also, the traffic jams were huge.

[1] There used to be parts which were also called N2, such as the part between Eindhoven and 's Hertogenbosch (Den Bosch). This has been rebuild and has become A2 somewhere in the 90s. After that project (I don't remember exactly when), they rebuild the N2 in Maastricht to become A2.

[gpvos]

There is still a motorway with traffic lights: the A59 is interrupted for a few hundred metres so it can have traffic lights at Knooppunt Hooipolder where there is an interchange with the (more important) A27. A major source of traffic jams. It is not signposted as having a different road number, although I guess administratively can't have an A number for that stretch.