Don't look now, but here's ANOTHER pilgrimage path to plan for!
The Camino Lebaniego Castellano is a newly waymarked bike and hike path that connects the city of Palencia to the shrine of Santo Toribio de Lebaniego, up in the Cantabrian mountains. It is waymarked from south to north, and crosses the
Camino Frances at Boadilla del Camino. It joins the Camino Vadiniense at Potes.
The CLC follows the Canal de Castilla up into the mountains, joins the waymarked Romanesque Route to towns with spectacular Romanesque churches and monasteries (you stay in one, San Andres de Arroyo). The Way is just over 200 kilometers long, and is cut into 11 etapas -- you can cut off the first two or three days if you join it at Boadilla.
Etapas are not terribly long, but a couple of the final days include heavy inclines and descents. Accommodation is a mix of casas rurales, pensions, hostals, and one or two albergues. You'll have to carry food a time or two, and be prepared for any kind of weather. A phone will be helpful, for calling ahead to reserve rooms; you WILL need some useable Spanish for this trail.
I haven't walked this trail (YET!) but I know the countryside and some of the towns. It ought to be a wonderful trip, especially in Autumn when the leaves are turning color. I think the mountain bit could get impassible in Winter, unless you don't mind walking along secondary roads. At the end of the trip is the monastery of Santo Toribio de Liebana, a medieval pilgrimage site and home to the "Lignum Crucis," supposedly the largest bit of the True Cross of Christ in the world.
Turismo de Palencia waymarked it; I have seen the posts in Grijota and Fromista. The
.pdf is available here At least some of the path is downloadable on Wikilok.