I would be happy to clarify, as this particular bit of the camino is a bit of a sore spot for me. Living in Santiago, and once upon a time having work near Arzua, I drove this stretch of road twice a day.
The town of O Pedrouzo is the last city of any size before Santiago and for many many pilgrims it is the last night before arriving. The crux of the problem is that the city isn't on the official camino in the strictest sense. It is 100m south of the camino.
The first trouble begins at the entrance to town where all day long pilgrims arrive to a junction with the N-547. Their options are to cross the N road and keep on the camino as it goes slightly north of town, or to turn left and follow the N road into town. Which way you should go depends entirely on where you are staying; for example the municipal albergue is the first building on your left when you follow the road. Other pensions may be closer to the official camino option. Adding to the confustion are 2 dozen accommodation signs doing their best to lure you to their property.
I should add now that following the camino into the forest to the north of town doesn't mean you miss the town. There is a road which connects it at the closest point and is only 100m (ish).
What this means is that everybody that stays the night in town needs to get back to the camino somehow. This is easy if you crossed the N-road because you know where the camino is and can just retrace your steps. However if you turned left to go into town you are left with the feeling that the road is the camino; and there are only 2 arrows indicating otherwise (on at the yellow correos box and another at the end of town which directs you to San Anton). These arrows are difficult to find and in the case of the latter arrow it is on the wrong side of the road for pilgrims who have been diligently abiding the Peatons on the Left signs.
Pilgrims who go back to the camino walk the "enchanted forest" portion of the camino, 3km or so to Amenal. Pilgrims who stay on the road walk the road. They walk with their back to the sun, and in the early morning oncoming traffic (I know) is staring into that sun. It is a recipe for disaster; already there have been fatalities at the start of town with so many pilgrims trying to cross the N-road (which is technically illegal outside of a crosswalk).
More arrows, and better directions by the albergue owners, could easily solve the problem.
Attached is a map to illustrate the route. The circles are accommodation.
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