Very beautiful country, up there in the north of Spain. Haven't been, myself, but have lived and traveled around the U.S. northern and western states for decades, often coming across views like that. Some more forested, some more steep and not so, um "mature" looking.

The landscapes where you were look very much like parts of the Basque Pyrenees. (I guess it is, on the western edges of the Basque mountain areas.)