Santillana del Mar is a beautifull medieval village, and to preserb that is not allowed to go inside the village by car. Only locals are allowed to drive in, so if you arrive to the place by car you´ll have to park in one of the park areas provided in the outskirts. I did´t pay for park, but I don´t know if it´s like that all the year.
Don´t worry about that, in Santillana everithing is five minutes walking from everywhere!!
As in the rest of the small places around the world, this is one of the favorite pasttimes for the locals. I think in Santillana, they must have a lot of fun watching the tourists with their funny habits and outfit.