This is a Federal highway, and as you can tell, all of the cars are riding the shoulder.
This highway is littered with signs saying “ride the shoulder, allow overtaking”
In this snapshot, the google earth car is overtaking the white Honda, and two cars going the opposite way are riding the shoulder so that it can pass. When you wish to overtake here you must put your turn signal, and then flash your brights, this is the sign for cars going the opposite way to start riding the shoulder, or to tell you that they won’t let you pass.
I find it disconcertingly unsafe, some find it very practical.
The crossing speeds are upwards of 200km/h, since the speed limit is 110km/h, but I assure you most people are going quicker. On the other hand, the entire road is always clean because of cars driving on it all the time, so riding the shoulder is not dangerous.