The history of the exploitation of the pastures in Val d’Ossola is documented since the first half of the year one thousand. The Ossola mountain offers , even at high altitudes , vast expanses and well sheltered from the winds for grazing animals and , from these characteristics , the local mountain dwellers through the centuries have been able to take advantage of great cheeses . Very limited productions , a few hundred forms each year , they work in the months of July and August and made back down to the valley by mule or , in recent years , by helicopter .