Valdediós

This is the monastery of Santa María de Valdediós, built in the early 13th century, a few km south of Villaviciosa, directly on the route of the Camino de Santiago. The church of Sta María is accessed through the archway, and it´s older stonework can be seen behind and to the left of the arch.

In the same area is the 9th century church of San Salvador, which Wikipedia among others may confuse with Santa María. This site, for example, includes photos both of Sta María and of San Salvador labelled as Sta María:
 https://www.turismoasturias.es/en/descubre/cultura/patrimonio-religioso/santa-maria-la-real-de-valdedios
 
Sta María is a church and a monastery. It was until recently the home of an order of nuns, it is a tourist centre (closed currently by covid 19), and it is an albergue on the Camino de Santiago. 

In the Civil War it was the site of a hospital which treated people from both sides. In retaliation, Franco´s troops murdered the staff. The common grave is in the field behind.