The Baztan Valley and Bidasoa Valley do not have a particularly harsh climate or aggressive terrain and the highest mountains range between 1000 - 1300 metres in height. Nevertheless the craggy peaks often make the area seem more intrepid than it is and marauding armies have usually scuttled through the mountain passes en route to the more fertile flood plains to the south.
The area is wooded (which, for centuries, has offered welcome tree cover to smugglers and refugees crossing the border by night). However, unlike the central Pyrenees, the trees are mainly deciduous with a predominance of oak, chestnut, ash and walnut trees along the valley floor and beech trees on the higher ground which means that we enjoy glorious kaleidoscopic autumns of reds, oranges and golds. This is also wonderful foraging country, and in the autumn walkers find walnuts, chestnuts, hazelnuts and figs on the trees. However, the greatest foraging tradition of them all is mushroom hunting with particular reference to the Boletus Edulis (cep). Here locals secretly guard their favourite mushroom-picking spots which are often handed down through the generations.
On the higher grounds walkers find herds of sheep and semi-wild ponies (pottoka) - a native breed of the Basque Pyrenees. These animals are often found roaming freely as in some areas up to 80% of the land is common ground. In the denser forests there are wild boar and on the south-facing cliffs of the Baztan valley there are the most northern (natural) griffon vulture breeding grounds in Europe. Bird lovers will also find the Spanish imperial eagle, red and black kites as well as white-backed wood peckers and king-fishers. Badgers, roe deer, ferrets and red squirrels are also common.