This motorway, between Vila Real and Amarante in the north of the country, was launched in 2008, by the Socialist government of José Sócrates, as a public private partnership. The franchise agreement was signed with two construction companies Somague and MSF.

But progress was not easy and the work to excavate the Marão Tunnel, the longest in the Iberian Peninsula with 5.6 kilometres, was suspended twice because of an injunction filed by a company that produced water in the mountains.

In July 2011, under the government of Pedro Passos Coelho, work stopped along the entire motorway because of financial difficulties by the franchisee.

The Marão Tunnel will go down in history as the first public work rescued by the state, which happened two years after the works ground to a halt.

The Infrastructure manager launched three international call for tenders to complete the work in February 2014, to build the eastern and western approaches and to finish digging the tunnel.

Building work was supposed to finish at the end of the first quarter of this year and the work is going to be inaugurated on Saturday by yet another prime minister, António Costa, and open to the public at 0:00 on Sunday.