In Cantabria there is a large number of fortified towers that fulfilled housing and defense functions, and in their time they were "very numerous".[1]​ These constructions, generally crenellated, were mostly erected between the 13th and 15th centuries by noble families and had a notable influence on mountain architecture, with some becoming fort-houses, a prelude to the future mountain mansion.[2]​ A curious fact is that they do not exist in the region. circular towers (except in some churches), as occurs in the neighboring community of Asturias.[1] Currently, the majority of this type of towers that still stand are either in a deplorable state of conservation or have been tremendously transformed.

The towers and castles, which appear in medieval documents as castellum, were very popular both as fortresses and residences of noblemen, mayors and lords, and ended up becoming widespread in the lower valleys of Cantabria, being built on the hills and in the towns; One of the best examples of urban towers that gave rise to towns is the missing Torre de la Vega "Torre de la Vega (Torrelavega)"), the genesis of Torrelavega.[3]​.

The defensive towers of Cantabria, due to their architectural characteristics, can only be compared with those of Encartaciones, a neighboring region of Vizcaya.[1]​.

Early medieval fortifications

In the territory currently occupied by Cantabria, three stages can be distinguished in medieval military architecture. The first, around the 7th and 12th centuries, is documented with around twenty sites that correspond to small castles, presumably linked to two alfoces "Alfoz (urbanism)"), and which constitute the first organization of the Cantabrian territory of a non-monastic nature. These castles are located in high places, easily defendable and often visible from each other. At the end of the stage the new castles, related to the founding of the four towns (Castro Urdiales, Santander "Santander (Spain)"), Laredo "Laredo (Cantabria)") and San Vicente de la Barquera), are now more complex and are located in the same urban centers. Successively renovated, centuries later they will star in the third phase along with the walling of the towns.[4]​.