It covers an area of 695.9 km2 (268.7 sq mi), occupying the Districts of Viana do Castelo, Braga, and Vila Real and bordering the Spanish Baixa Limia – Serra do Xurés natural park to the north, with which forms the UNESCO biosphere reserve of Gerês-Xurés.

On the other hand, the precipitous valleys, crossed by high flowing streams, host lush temperate broadleaf and mixed forests of oak and pine, being one of the last strongholds of the typical Atlantic European flora of Portugal, contrasting with an evolving Mediterranean biome.

[5] The aims of the park are to protect the soil, water, flora, fauna and landscape, while preserving its value to the existent human and natural resources.

[8] Human activities consisted of animal husbandry and incipient agriculture, and archaeological evidence points to the beginning of a decrease in forest cover.

The Germanic tribe of the Buri accompanied the Suebi in their invasion of the Iberian Peninsula and establishment in Gallaecia (modern northern Portugal and Galicia).

187/71, 8 May 1971) envisioned a planning area of mountainous spaces, in order to conserve the environment, while permitting human and natural resource activities, which would include educational, touristic and scientific projects.

At heart is the conservation of soils, water, flora and fauna, in addition to the preservation of landscapes within the vast mountainous region in the northwest of Portugal.

[10] In 2007, it was accepted in the PAN Parks network that certifies the quality protected areas, according to rigorous criteria of nature conservation, cultural services and sustainability.

The highest peaks are Peneda (1340 m), Soajo (1430 m), Amarelo (1350 m), Gerês (1545 m) and Altar dos Cabrões (1,538 m) located on the border with Galicia, continuing into this territory as part of the Serra do Xurés.

[11] Sedimentary layers laid down between 435 and 408 Ma (Silurian epoch) were deformed and metamorphosed into schists, greywackes and quartzites (such as in the area of Castro Laboreiro).

[11][13] Generally, the lithological structures can be divided into three layers:[14] During the Pleistocene (approximately 1.8 to 0.001 Ma ago) climatic variations resulted in an extension of glacial fields to the mid-latitudes.

[12][13] The Lima cuts across the PNPG east to west, while the Cávado serves the southern limits of the districts of Vila Real and Braga.

[11] Owing to the number tributaries, the construction of hydroelectrical dams has been undertaken to generate electricity across six locations: Alto Rabagão, Paradela, Caniçada, Vilarinho da Furna, Touvedo and Lindoso.

Soils within the elevated terrains and inclined spaces are non-existent, while the valleys are rich and deep, deposited and transported by pluvial action.

[15] The elevated levels of incompletely decomposed organic material, low in phosphorus and intermittently low/high in potassium, are subject of alluvial deposition.

[15] Its climate is greatly influenced by the topography; the mountains exert a barrier effect to the passage of hot and wet air masses coming from the Atlantic Ocean, resulting in elevated precipitation throughout the year.

[24] In upper altitudes there are patches of European oak that enter into their own association (Holco-Quercetum pyrenacia), which is integrated into another group (Quericon robri-patraea).

[26] There are 627 flora species identified by Serra and Carvalho (1989) as under pressure and considered endangered, which included two medicinal plants: tutsan (Hypericum androsaemum) and sundew (Drosera rotundifolia).

There were also registered sightings in Albergaria, Lamas de Mouro and Serra da Paneda, while comparable encounters in Spain were identified across the border.

[29] Meanwhile, other mammals, such as the population of Iberian wolf (Canis lupus signatus) have collapsed with human encroachment, while the number of exemplars are limited.

[29] Brown bears disappeared from the region in the 17th century, and the extinct Portuguese ibex (Capra pyrenaica lusitanica), locally known as Gerês goat, was last seen in the 1890s.

More than a century later, its vacant ecological niche was reoccupied naturally by Spanish ibex coming from Galicia, and their population numbered about 100 animals by 2011.

[29] For a long time these horses permeated the farms of Vilarinho das Furnas (before it was inundated with the dam's construction), but later began to freely move between the Portuguese-Spanish border after 1979.

[29] For the winchat, the area of Mourela is the unique nesting ground in Portugal, while the red-backed shrike and yellowhammer are limited to Castro Laboreiro plateau and northern corners of the park.

Also important to highlight is the gold-striped salamander (Chioglossa lusitanica) a species endemic to the northwest Iberian peninsula, typically associated with mountainous areas with elevated precipitation.

Terraces, built to make better use of these scarce lands, and traditional houses, with granite walls and thatch roofs, shape the landscape with an indelible, harmonious, human mark in some of the most isolated villages such as Pitões das Júnias and Ermida.

[43] The inaccessibility and diminished exterior investment potential, has concentrated those activities in the region primarily in the exploration of forestry, the support of hydro-electrical generation and tourism.

The cattle enjoy a purity of nature that is characteristic of these places, contributing greatly to the preservation and biodiversity of the landscape as well as to the rural economic sustainability.