The Verbano Cusio Ossola Province is located in the central western Alps and has had great importance for geological studies about the Alps since the last century.
The Alps are a double-vergent chain : an European one and an African one, the southern Alps divided by an important tectonic line named Lineamento Periadriatico or Insubric Line...

Milan Cathedral
In this area another factor has made this stone important both with regard to extracting and to the diffusion of the product: during Medieval stone materials, essentially marbles, could reach places like Milan and Pavia, where they were highly desirable to create ornaments. The transport was quite easy: by waterways. (Toce, Lake Maggiore, Ticino, Naviglio (Canal).

Pinauda in 1928 gave this definition:
“The Milan Cathedral, one of the wonders of the modern world, is nothing but a mountain made of ossolano marble artistically carved”.