I'll paste what I had written on your previous post:

"Do you live in Spain (as written in your profile)? If so, note that the Global Pass restricts you to 2 days in your country of residence.

Other than that, yes you’ll need reservations for some journeys. The AVE from Barcelona to Narbonne is only available at Spanish ticket counters but there are TGVs on the same route too, those are available online.

Here’s an extensive guide on the topic: https://www.seat61.com/interrail-and-eurail-reservations.htm

As your trip focuses on Spain (one of the worst countries for Interrail/Eurail) it might make sense to get tickets instead. It’s your choice."

Basically you should compare whichever is cheaper between individual tickets vs passes + seat reservations. Note that Interrail is not valid on Euskotren services (Hendaye - San Sebastian - Bilbao). Tickets are fairly cheap anyway.

Side question but why are you driving from Asturias to Porto? One-way car rentals are notoriously expensive. There are trains on that route, although not frequent but certainly doable! :)

For example:

- Oviedo - Ferrol 07:30 - 14:44 -> very slow but extremely scenic along the coast

- ARC Ferrol - La Coruña 15:10 - 16:16

- MD La Coruña - Vigo-Urzaiz 17:00 - 18:26

- easy walk between both stations, little break

- Vigo-Guixar - Porto 19:56 - 21:18

Thanks for the quick response.  Very helpful.  Regarding Asturias to Porto, I couldn’t find any service, so thought I’d rent a car and drive.  I’ll look at the route in your example - seems like a very long travel day.

Much appreciated.

You could also "cheat" by taking the ALSA bus from Oviedo to A Coruña: 10:00 - 13:35. Then a fast train to Vigo before the evening service to Porto. :)

I guess I'd do that, although the little route along the coast seems very tempting haha