To explain and understand this route, you need to mentally go back to the 9^th century. In that early medieval period, there were Christians along the Cantabrian mountain range,  while there were Muslims on the Castilian side. Due to the weakness of the Emirate of Córdoba at that time, the Muslims suffered several attacks and started to retreat south, thus leaving an uninhabited strip north of the meseta. Some documents date back to the year 814, when people in the north crossed the Cantabrian mountain range to repopulate those uninhabited areas. This repopulation movement would begin in various areas in the north of Spain; and nowadays, Castile is a land of opportunity for many.

In the case of the Saja Nansa region, the starting point was Mazcuerras and Cabezón de la Sal, and it went around the entire Saja valley. It’s what is known as the Route of the  Foramontanos.

The route goes up to Brañosera (Palencia). In a document dated back to the year 824, Count Munio Núñez granted Braña Osaria a Municipal Charter called “Fuero de Brasoñera.” The document’s purpose was to organize the repopulation by recognizing the settlers’ rights to the land. In it, he makes reference to the “the road that Asturians and Cabuernigos used to travel.”

More information in Route "Los Foramontanos"