Asturias-Cantabria-Basque itinerary advice

Santander has nice beach views but I thought it was otherwise unremarkable. You'll have a car and have no need of it as a base for side trips.

I found Potes charming, though there were certainly tourists walking around. I have no reason to urge you stay there rather than elsewhere, however.

I was glad to spend a bit of time seeing Santillana del Mar, but it is extraordinarily touristy. It helped me to know that ahead of time.

Comillas has some modernista buildings, if you are interested in that sort of architecture.

I'd recommend prioritizing your key outdoor activities as you get to each area, because the weather tends to be cool and overcast. Your first day might be the best--though I don't remember significant downpours.

Olite is just over a two hours drive from Bilbao, so the distance isn’t all that far and the castle in Olite is spectacular. There are a number of places to visit in the Logroño area, Estella, Puente de la Reina, Briones, San Vicente de la Sonsierra, to name a few. We enjoyed Cangas de Onis by the Picos de Europa. Santillana de Mar is best seen after the day trippers leave when you have the town to yourself. I haven’t been to most of the small towns you mentioned, but driving that stretch of coast doesn’t take very long in the grand scheme of thing, so don’t rule out places a little further inland.

Edited: another plug for Olite are two wineries in the town itself; Bodegas Vega del Castillo and Cosechero Reunidos Coop. There are others just outside of town.

I seemed to be the only foreign tourist in Olite when I spent a night there in 2016. It has a back-of-beyond feeling that's quite a change from coastal towns.

1. If you had to pick between Cudiellero (Asturias) and Leikito (and around, Basque County), which would you pick? Wondering if I should give up a night in Asturias and add it to the Basque region? (Don’t care about seeing San Sebastian this time).

Lekeitio is a hidden gem, I used to spend there my summer vacation as a kid. Love the place, but Cudillero is also beautiful. Ondarroa is also worth a visit and totally off the beaten path. Elantxobe, Ea, Natxitua...all on the route to Lekeitio and well worth a stop.

Olite sounds great but might be a little out of the way for this trip, unless gas price go way down in the next few months. Might focus on spending more time in the north and allow a little extra time there to account for bad weather.

Does it make more sense to park it in one place and drive to sites (like staying in Cudiellero and driving to Ribadesellas for a day), which means more driving, or move along to different hotels along the route which is less driving but less flexibility for weather?

Don’t let the gas prices prevent you from going someplace you might want to visit. In May we rented a car in Madrid, headed south and did a loop, Chinchón, Alarcón, Teruel, Zaragoza, SOS Del Rey Católico, Olite, Santo Domingo de la Calzada, Soria, Sigüenza, Alcalá de Henares, and back to Madrid. We had it for 22 days and took days trips from all the towns we stayed in. In total we put about 2,000 kilometers on the car and the total we paid for gas was $315.91. At that time the exchange rate was 1€ - $1.04, and gas prices varied between 1.5-1.65€ per liter. Currently, the average across Spain is 1.69€ or about $6.80 a gallon at the current $1.06 exchange rate. You wouldn’t be driving anywhere near that distance. The cost of gas is nominal when considering the overall cost of the trip.

If you don’t want to double back at all, then stay in towns along the route rather than using one as a base. Once you have the places you know you’re visiting identified, find a town and check distances from it to the other places you intend to visit. You may well find that there are X places within 30 minutes or so of town Z. In that case it makes sense to use town Z as a base to visit the other places. If you find a town you can use as a base for a few days, that would save having to pack up and move every day. It’s really a personal preference.

Jaime- thanks for the gas prices. That helps puts things into perspective. It’s not much given the very high flight prices!

Our 5 days in the Basque Area was not enough thanks to our guide. Mikel..Contact info :Toursbybasques.com or text/call via whatsapp 34 618 55 03 95. He is Secretary of the Basque Country Tour Guides Association
I communicated w/Mikel for 2 yrs before we actually made the trip this Oct due to Covid.
Mikel was the most amazing, well informed, professional guide we have ever had. We stayed in Bilbao and took daily trips via his car. (This is a plus as most times you pay extra for a driver but Mikel was both) Of course we toured Bilbao on foot w/Mikel, then took the funicular to have a look of the city from the top..Amazing. His recommendation of Restaurante Txakoli @ the top was super.
The next days were driving to amazing cities. Yes, everyone talks about San Sebatain which we went to. But, for us the small towns were priceless. Mikel picked Getaria, a small fishing town. We ate at May Flower which overlooks the town. A must
Another day was Guernika, made famous by Picasso. Onto Bertron, Castillo de Burton..12th century castle and ending in Plentzia for lunch. Stopped in Getxo too. All towns that Mikel suggested, that for us, were more beautiful, historical and easier to get around then San Sebastian.
Another day was spent in Haro, the wine area for Rioja. The wineries Mikel picked were small family owned Bodegas. In one they took us down into the caves that their ancestors had used for centuries for wine storage. Laguardia was our last stop. This town made us feel like we were in a movie. Old with small streets, beautiful shops and lots of history.
We couldn't have done this with the ease we did w/out Mikel. If you like histrory, great food, restaurants then Mikel is your person. Yes, people say you can do it on your own BUT you learn so much more w/a guide. We are going back next Oct to see new areas because Mikel made our trip so easy.