A long story with a happy ending

The history of the Salerno-Reggio Calabria is an 82-year-long epic (54 years of work). That is why many have dubbed it the eternal work. Its first appearance in the annals dates to 1934, when the Italian Highway Master Plan called for the construction of the Livorno-Civitavecchia-Salerno-Reggio Calabria Tyrrhenian highway. But the project did not start.

In fact, the construction program for the former A3 (new A2), the Salerno-Reggio Calabria, with a budget of 100 billion liras was only approved by law in 1955 and work started in 1962.

In 1967, 125 km from Salerno to Lagonegro were already in operation, but for the remaining 318 km, many difficulties were encountered. In fact, the A2 is the highest highway in Europe, with an average elevation of 1,000 meters above sea level and 100 kilometers of tunnels, as well as numerous viaducts built by the best engineers of the time, in the arduous Apennine environment.

The last section was opened in 1974, with a final cost of 368 billion liras. After 40 years, therefore, a happy ending. But no. Things turned out differently, continuous construction sites and detours made it for another 40 years, an interminable, modern and proverbial "St. Peter's factory," finally finished and opened to traffic in all 440 km only on December 22, 2016. Three of the toughest engineering challenges of the infrastructure, which crosses the South, are the renovation of the Sfalassà Viaduct (in 2008) and the Favazzina Viaduct (in 2013). 

But let's go in order. The Sfalassà Viaduct is suspended 249 meters above the stream of the same name in the Bagnara Calabra valley, with a single central metal span that is 376 meters long. It had been built in 1972, and in that year awarded the European Metal Construction Convention. It is 769 mt long and has 125 mt high supports embedded in an area of high seismic risk. The solution that allows the deepest part of the gorge to be bypassed in a single leap is a mixed prestressed concrete structure, from which the spectacular metal portal span departs.

The Favazzina Viaduct, on the other hand, was designed in 1974 by engineer Riccardo Morandi, with two structures suspended between the steep, lush valleys at the tip of the boot near Sicily. It is 449 mt long, 150 mt high from the valley floor. It is curvilinear from start to finish, the deck is made of a mixed steel and concrete system, supported by huge piers planted in the valley, about 55 to 92 meters high.

In terms of engineering, it is considered among the most significant viaducts in Europe, in a deep valley surrounded by steep mountains, with 1.5-meter raised parapets and fall-prevention nets, an approximately 80-meter-long cap, secured to the ground by 10 thousand nails, allows the new viaduct to "cling" to steep slopes. 

In both viaducts, old materials were removed, and the mountain slopes and riverbed pockmarked by construction sites were renatured with trees and vegetation.