The Montaña OrientalSpecial Area of Conservation (SAC) is located at the eastern end of the Cantabrian Mountains, covering the headwaters of the Pas, Miera and Asón rivers.
It includes the massifs of Castro Valnera to the southwest, Alto Asón in the central sector and Sierra de Hornijo on the northeastern end. In its interior is the Collados del Asón Natural Park.
It is the highestmountain massif in theeastern Cantabrian. The nature of these massifs is terrigenous to the southwest, becoming progressively calcareous towards the northeast.
In the limestone cliffs nest up to five species of birds of prey:golden eagle, Egyptian vulture, griffon vulture and eagle owl.
Theimportant karst formations stand out, covered with scrub and sclerophyllous forests, which give rise to subway cave systems.
A natural treasure in the Cantabrian Mountains
The Montaña Oriental SACis located at the eastern end of the Cantabrian Mountain Range, covering the headwaters of the Pas, Miera and Asón rivers, and integrating the massifs of Castro Valnera, Alto Asón and Sierra de Hornijo.
It is the highest mountain massif of the eastern Cantabrian, with a varied geology that includes terrigenous and calcareous soils.
This area is home to the Collados del Asón Natural Park, an area of great natural and ecological value where you can enjoy the beauty of different types of landscapes, as well as a great variety of ecosystems, flora and fauna.