Tresviso I (La Mesa), Cantabria (2016). After the fall of the northern front on 21 October 1937, many fighters fled to the Asturias mountains, forming guerrilla groups in the most rugged areas such as the Liébana Valley.
After the fall of the Northern Front of the Civil War on 21 October 1937, many fighters were scattered throughout the mountains of Asturias and, having been trapped, tried to return to their places of origin in Asturias itself, in Santander, in León and in Palencia. Some of these fighters stayed in the mountains and would form parties of Maquis, Spanish guerrillas, in the most mountainous areas like the Liébana Valley.
