This route was the actual Camino route until a couple of years ago, before the riverside route was marked. Take it only if you plan to spend the night at the very highly recommended albergue in Xagoaza. I am not sure if the route is still marked through the town of O Barco, but it is easy to get to. Make your way to the railroad underpass at the end of Calle Eulogio Fernández, where you will see a blue Camino sign pointing your way west. At the roundabout just past the Repsol gas station turn left onto Rúa Estrada. At the modern Church of San Tirso, turn right. Then keep straight, and go through a narrow tunnel. Up ahead there is a marker pointing up to the hamlet of Xagoaza. Pay attention, because a 2016 pilgrim reported that there are no arrows to indicate the turn. You will return to this spot to continue on the Camino.
Albergue Xagoaza (Hospitalera, Gloria, tel. 639 921 679). This albergue is several km outside of Barco, and 1.4 km off the Camino. The hospitalera may provide meals if needed, but it is a good idea to bring your own food from O Barco, just in case. Reported quite nice by many pilgrims. Two rooms with 5 bunks each, large dining room with fireplace, two PCs and Wifi, completely furnished kitchen with stove, oven, fridge, and washing machine. Clean bathrooms and lots of outside space. 6€
Coming down from the Albergue you will join the camino at a point where it becomes an earthen path. This path may or may not be overgrown (pilgrims at different times of year had different reports), but you should continue straight ahead. You will arrive back on the road, having gone around a nicely renovated home.
When you come to a metal sign with the words “Asociación de Desenvolvemento Valdeorras”, you have a choice. You can either go straight on the road or turn left. If you turn, you will soon come to a faint arrow on the ground, which turns off the road onto a dirt track. This is just before a gravel pit of some kind. When you get to the top of the pit, you will come into a clearing with a lot of grape vines. Turn left and keep on into Arcos, with the grape vines on your right.
If you have decided to go straight at the earlier mentioned metal sign (recommended), it takes you to a paved street, where the arrows take you right for several hundred meters (this option was described by some pilgrims as “easy but boring”). Either way you will arrive in Arcos.