This first section of the Po river Park includes the mountain area of the river, and it covers a surface of 7,709 hectares on an altimetric altitude between the 250 and the 3,841 meters above sea-level. In only eleven kilometres the river Po runs through the 700 meters of difference in height dividing its sources from Paesana, the "regional capital" of the valley. Starting from the sources, the vegetation is rich and various, while starting from Crissolo the river course is bordered by some high-trunk trees; going down towards the plain we can meet step by step different species, from the conifers to the broadleaf trees, to some essences such as larches, birches, beech trees, chestnut trees, willows, and black alders.