Providing the weather is good in the Bay of Biscay that's a lovely crossing, to me it felt more like a little cruise than a ferry ride. I personally took the early evening crossing which arrived in Santander early the next morning. The feeling of being on a cruise seduced me into to a rare moment of indulgence, treating myself to meal in their relatively posh restaurant instead of their café. After a quick explore it can be a challenge to find things 'to while away' the time on a ferry; I concluded that a lovely meal, lovely bottle of wine and a lovely view was a good way to spend the evening; for sure it can be easy to talk myself to an indulgent treat! A full tummy and no doubt the wine I dare say more than contributed to me sleeping through the overnight storm that everyone was complaining about as we waited to cycle off the following morning
Many use that crossing and then ride towards the Pyrenees. I personally went along the coast in the opposite direction and spent a few days in the
Picos de Europa National Park; a tour I rode over 30 years ago and remains one of the best I have ever done, the ride from
Panes via Potes to Fuente Dé with a trip to the top by cable car was a highlight; can't recommend it enough