The Ossola valleys are internationally recognised for their stone: the granite, marble, beola and serizzo that have left an indelible mark on the landscape and the local economy. The architecture of the area is largely based on these local types of stone, which are everywhere on display in houses, streets, flowerbeds and monuments. 

That this is an area with a wealth of stone is immediately evident from the number of stone quarries seen throughout the Ossola. Stone began to be cut, sold and exported during Roman times, and the tradition has continued down the centuries to the present day, thanks to the hard work and skill of the local stone masons, called in the local dialect “picasass”. 

Stone was regarded as a humble material, but has been processed and used in so many ways over the years that it has helped develop a strong cultural heritage, a sort of symbiosis between the valley and its stone resources, to the extent that it represents a sort of historical memory of the area.

The whole Verbano Cusio Ossola area can be viewed as a major geology park, and is studied by the Geology Department of Milan University on account of the innovative quarrying techniques used.