Bilbao to Barcelona

Direct daytime trains run twice per day and take 7 hours. That's probably my first choice, or you may find a flight at a good price. How to Look Up Train Schedules and Routes Online gives you the DB train schedule link and tips for using it. Actual tickets are sold at www.renfe.com starting about two months ahead, maybe three, easiest to pay with PayPal instead of credit card. For flights, see www.skyscanner.com.

By contrast, it's about a 1 hour flight (see Iberia and Vueling) or approx 6 hour drive (with heavy tolls).

Everyone has their own priorities, but having spent a week in Bilbao before the museum was built, I wonder if you should leave Bilbao out of your itinerary. Spain has plenty of fading post-industrial cities, just like the United States. It's off the beaten track. (Opinion)

We are simply flying into Bilbao, as my husband has a cousin who lives in San Sebastian. We will be visiting many different areas in the Basque provinces that include his relatives.

Also thanks for the information "Laura".

we just flew from Barcelona to Bilbao and then took the bus to San Sebastian. It was quick and easy!