Always wanted to see Portugal. We had been on a Rhine River cruise and were easy "converts" to river cruising. Having mentioned the Rhine, our only "criticism," if that's the right word, is that the scenery on the Douro is quite monotonous, i.e., vineyards, olive trees, almond trees, vineyards, etc, etc. One sees little life on the Douro probably because this was Spring and not the fall harvest. This is not a criticism of Viking. They can't change that. But we did enjoy the boat and the many people we met on it !
Weather was absolutely glorious even in Santiago which was optional where I had been told by a friend "it always rains." It didn't.
Service on the Osfrid was quite good. Staff in the dining room was exceptional especially our waiter Augustin and the Maitre' d Dragos.