The various difficulties, both constructive and architectural-environmental, due to the several restraints posed by a heavily built-up territory, have been solved thanks to integrated solutions adapted to the orographic and landscape context of the surrounding environment. The definition of the works of art has been strongly influenced by the importance of the territorial context reflected in the choice of valuable constructions, in particular in the most sensitive areas. The viaduct structure ranges from mixed two-beam decks made of steel/concrete to half-through arch bridges. The tunnel entrances, located in small narrow valleys, consist of reduced length portals with continuation walls lined with natural stone.
The design of the underground focusses on the aspects of user safety in case of emergency (specific plants and structures, including the presence of an escape pedestrian gallery under the road surface).
The work, due to the very nature of the areas involved, poses mainly environmental problems; although 70% of the route develops in tunnels, environmental compensations and mitigations are an issue in the open-air stretches in small valleys or heavily built-up areas.