Hi.. we are a couple traveling to spain in the first week of oct. in barcelona for 3 nights on work. wanna spend another 6-7 nights in spain for tourism. can drive to the north from barcelona to san sebastian / santander etc.. we prefer nature / nice drives/ mountains alongwith interesting places to visit.
please advise.

Are you flying out of Barcelona as well?

Have you thought about driving along the coast towards Malaga?

There is no need to drive very far - the region around Barcelona is very scenic.

Very close to Barcelona, you find Montserrat ("split mountain"), a scenic place with a beautiful church.

The coastal road northwards is very scenic, with lots of picturesque coves and charming towns. Tossa de Mar is especially beautiful.

Further northward, you reach Cap Creus - a most bizarre scenery. Stay for two or three nights in Cadaques, Spain's most beautiful White Town. There are several things to explore in the region, including the Salvador Dali Museum in Figueres and his house in Port Lligat.

Then head further northward into the Pyrenees. On the French side at the coast, Collioure is a charming town. In the inland, Ceret is very beautiful. From there, you can drive tiny roads up the Mont Canigou and continue hiking when the road ends.

The drive on either side of the Pyrenees in early October will be nice with the fall colors. The most scenic route would take you up through the Val d'Aran. You can easily spend two nights on the road, the first in Val d'Aran. The Hotel Mauberme in Salardú would be nice if they still have availability.

From there you can drive to Tarbes and Pau and into the Pays Basque, crossing back into Spain over the pass at Saint-Jean-Pied-de-Port. The N-135 will take you to Pamplona. It's an hour drive from there to San Sebastián-Donostia.

The other option would be to go on to Saint-Jean-de-Luz from Saint-Jean-Pied-de-Port and then cross back into Spain on the A-63.

Thank you all for your input .
We are flying out of Bilbao .
This way we can spend a week (over and above Barcelona) in the northern region of Spain and also drive around the Bordeaux region in France .
So picking up the car in Barcelona and returning in Bilbao .
Have noted the advise given by traveller1959 & Robert .
Please add I case anything interesting comes to mind .
Highly appreciate your suggestions .
Thanks

If I am not mistaken Montserrat, gets it name from resembling the teeth of a saw, like the English word serrated.