Strada statale 131 Charles Felix
The Strada statale 131 (SS131),  is the major road in Sardinia, Italy. It is a freeway that connects the towns of Porto Torres and Cagliari via Sassari, Macomer and Oristano. At 229 km, it  is considered the "spinal cord" of Sardinia.
It is a part of the E25 European route.
|  | |
|---|---|
| Strada statale 131 | |
|  | |
| Route information | |
| Maintained by ANAS | |
| Length | 229.232 km (142.438 mi) | 
| Existed | May 17, 1928–present | 
| Major junctions | |
| From | Porto Torres | 
|  Strada statale 131 Diramazione Centrale Nuorese | |
| To | Cagliari | 
| Location | |
| Country | Italy | 
| Major cities | Porto Torres, Sassari, Macomer, Oristano, Cagliari | 
| Highway system | |
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History
    
Building works begun in the 19th century, under the Kingdom of Charles Felix of Sardinia, the road followed the route of the ancient Roman road Turris Lybissonis-Caralis.
The infrastructure was modernized under fascism, and in the 1970s was rebuilt, becoming a Superstrada (Dual carriageway), some stretches are classified a second category extra-urban road, and the speed limit is 90 km/h, while other ones are considered first category extra-urban road with higher speed limits (110 km/h).

