[jonknee]

> Mostly because in some countries it's not easy to tell when a speed limit ends and in my experience GPS maps are not always 100% accurate. Basically in most of EU the speed limit begins with a sign and ends at a nearest intersection, without any visible sign indicating so. So the car would need to recognize what is an intersection and what isn't - which is difficult even for human drivers, sometimes you have a paved road going off the main road to someone's house, but it's not an intersection so it doesn't cancel the speed limit. Again, it could be solved by having very very detailed maps, but then it doesn't help with roadworks which set up temporary speed limits.

My car today already tells me the speed limit. It's based on detailed maps and works great. There are many challenges to self driving cars, knowing the speed limit isn't a huge one. If anything autonomous cars are the opposite of speed demons.