The Aragonese Pyrenees is located in the north of the province of Huesca and is arranged longitudinally in three large units: High Pyrenees, Intrapirenaic Depression and Outer Ranges.
The Aragonese High Pyrenees contains the maximum heights of all the Pyrenees mountainous chain. The High Pyrenees is formed in turn by the axial Pyrenees and the Inland Ranges.
In the axial Pyrenees are the oldest materials: granites, quartzites, slates and limestones and the highest peaks like: the Aneto (3404 m), Maladeta (3,309 m) and the Perdiguero (3,221 m). The inner Pre-Pyrenees, composed of more modern rocks (limestones) also has large mountains such as Monte Perdido (3,355 m), Collarada (2,886 m) and Tendeñera (2,853 m).
The main Pyrenean valleys are formed by the rivers that are born there, which are:
Ansó Valley: Veral river
Hecho Valley: Aragón Subordán river
Canfranc Valley: Aragón river
Tena Valley: Gállego river
Broto Valley: Ara river
AÃnsa Valley: Cinca river
Pineta Valley: Cinca river
Gistau Valley: Cinqueta river
Benasque Valley: Ésera river
The intrapirenaic depression is a broad perpendicular corridor. Its best represented section is the Canal de Berdún. The southern limit of the Depression corresponds to the energetic reliefs of San Juan de la Peña (1,552 m) and Oroel Rock (1,769 m), modelled on conglomerates of the Campodarbe Formation.
The pre-Pyrenean outer ranges are in the Huescan foothills and constitute the southernmost unit of the Pyrenees; formed by predominantly calcareous materials, reach heights between 1500 and 2000 meters. The Sierra de Guara, one of the most important mountain ranges of the Spanish Pre-Pyrenees, stands out; its summit, the Guara Peak, reaches 2,077 metres. The Mallos de Riglos, near the town of Ayerbe, stand out for their beauty.