All of the region’s landscape is strongly marked by the presence of deciduous woods dominated by English oaks (Quercus robur) and Pyrenean oaks (Quercus pyrenaica), with other associated trees and bushes such as silver birches, yew trees, cork oaks, holly bushes, chestnut trees, arbutus trees, and butcher’s broom. The herbaceous stratum is characterised by its great diversity and high floristic value, with highlights being the European chain fern, the wild narcissus, scabious plants, anemones and paradiseas. Undergrowth, comprising bush and shrub communities largely of a substituting nature, also covers large areas of the National Park and includes species which, on account on their rarity, threatened status or endemic nature, are protected: for example – the Gerês iris (Iris boissieri), thymelaceae and armerias.

This botanical wealth, associated with the unique physiography, has favoured the formation of a group of natural habitats where we can find a great variety of fauna. Of the many species to be found here, the following are particularly noteworthy on account of their conservation status or their limited distribution area in Portugal: the Iberian wolf (endangered), the greater horseshoe bat (endangered), the golden eagle (endangered), Seoane's viper (rare), and the golden striped salamander (endemic to Iberia).

But the National Park is not only important for its natural aspects. This region has numerous features attesting to human occupation going back many hundreds, if not thousands, of years: there are megalithic monuments, such as dolmens and funeral mounds, from the first human communities; from the Iron Age there are remains of forts; a highlight from Roman times is the Antonine Way which linked Braga to Astorga (Spain), today known as the Geira; from medieval times we find castles, monasteries, bridges and some villages, now abandoned.

Today about 9 000 people live in the Park. The traditional economic activity of farming is now starting to give way to other activities but is still very important as a complementary activity. It has been this complementary nature between agriculture and grazing, between the valleys and the mountains, which has shaped the Park’s landscape over time. In a difficult environment, with a harsh climate, steep relief and with mostly poor soils, people have been obliged to make full use of the land, taking advantage of the different resources present at different altitudes. It is true that on account of their efforts to survive and adapt many natural features were destroyed (such as the original oak forests), but is also true that they created landscapes of great cultural and scenic value which show a harmonious relationship with nature. The villages, strategically located between the fertile valley areas and the forested and grazing areas; the terraces, notable rural engineering works; the water-courses; the walls; the “rega de lima” irrigation systems; and many other constructed elements (granaries, ovens, mills, shrines, etc) are all examples of a cultural heritage which we should value and look after.