Bus schedules in the Basque region

In the top right corner of the ALSA web page there is the word "Español", hover over it with your mouse and the drop down menu of various languages should pop up.

Carlos,
Muchas Gracias,
Pedro

Correct, Euskotren is not in English but the PDF versions of the schedules at http://www.euskotren.eus/es/viaja/horarios/tren are pretty straightforward. Be aware of alternate town names or spellings, such as: Pamplona/Iruña (different from Irun), San Sebastian/Donostia, Hendaye/Hendaia.

Rick's guidebook lists some destination-specific bus web sites in the Connections section of each chapter. For crossing the border all the way from Bilbao, if you need to do that, ALSA and FlixBus may not run every day; I saw some services limited to weekends. Depending on your destination, PesaBus may have more service; they have one direct, daily 7:00 a.m. bus from Bilbao making multiple stops around Biarritz (including the airport) and Bayonne before returning.

Pedro, que tengas un buen viaje, el País Vasco te va a encantar :)

... don't forget to practice your basic euskera (https://wikitravel.org/en/Basque_phrasebook). You'll get big smiles from our friends in the Basque region.

Enric, Eskerrik asko!

Carlos, Amare' a los vascos.

Laura, I have been using R Steves' Connections sections. Your comments were helpful. Since it is so early I cannot plan for next June's bus trips. Thanks

You are right, many of the local bus companies for that region have websites that are only in Castilian and Basque. You can use Google Translate; it's built into the Chrome browser, or you can find it at https://translate.google.com/.

I found a fair number of English speakers in the region, but many of the restaurants do not have English menus, so (assuming you cannot read Basque) be prepared to deal with Castilian menu terms.