I stayed Ferrol (two very interesting Navy/marine related museums, one with superb ship models.), Oviedo, Santander, Bilbao, Leon. The train to Leon leaves Bilbao early afternoon and arrives Leon quite late, but out of the town centre, with free...
I went Ferrol-Oviedo-Santander-Bilbao-Leon on the Feve, with stops of course. The Bilbao-Leon leg was superb. Cheap with tarjeta dorada. In Ferrol there is a dispenser machine, but other centres have a separate counter.
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