Quinto Real is a vast forest which is home to a variety of fauna, including the deer that surprise visitors in September with the "berrea" (the mating call of the stags).

Most of the Quinto Real forest is dominated by beech, with small clusters of oaks and alders along the river banks. Pines, firs and larches have been planted to fill in clearings in the natural forest, and the whole area forms one of the finest wooded regions in Navarre.