Posada Ansorena 

Stayed four nights. Dropped off luggage, then parked in tourist office car park - 5 minutes walk, and free (in May, at least). The posada is ideally located right in the middle of the town, and is a very attractive building very much in keeping with the rest of the town. In fact, when the tourist coaches have departed, Santillana del Mar is one of the most picturesque towns I have stayed in. The hostess at the posada, Andrea, was really friendly and helpful. The room was large, as was the bathroom, and both were spotlessly clean. The décor and furnishings are rustic, but comfortable. A bonus was the large balcony with a great view over the countryside. Breakfast was very basic, and boring if you're staying more than a couple of nights. Our big problem, however, was the dog in the garden of the property that barked all night. At least that's what it seemed like. There was another dog also, but Andrea was able to remove that one. Nevertheless, because the place has so many positives, and Andrea was so friendly, and because it is superb value for money, it stays as 5 stars.