Here in Switzerland we have to have a license to ride on the road. Minors must be accompanied by an adult 18 or over.
I ride on the road to get from point A to point B usually, however, there are times I do a "desensitizing" ride into town just to make sure my horses are able to accept different situations. My two biggest obstacles here are the cows with big bells on that come running to the fence to see you (usually the young ones but all cows here wear BIG bells around their necks). My mare is finally, after 3 years, calming down a bit. She wants to "flight" not "fight" and does not mind cows without bells at all. The other is flags blowing in the wind right when you come up to them. Cars, tractors, trucks, trains, helicopters, skiers, dogs, quads, deer, etc..............no problem.
Luckily people don't throw much out of the car around here......the Swiss do have their clean ways