Argentine President Cristina Fernandez has opened the 312km Rosario-Cordoba highway, linking capital Buenos Aires with Santa Fe and Cordoba provinces.
The state-financed project required an investment of more than 3bn pesos (US$355mn), according to the presidential website.
The four-lane highway begins in the city of Pilar and ends in Carcaraña. The route has dual-lane roadways in each direction, each measuring 7.3m, and separated by a 16m gap.
The route will improve transportation in an area that concentrates 70% of the country's GDP, as well as facilitating trade with fellow Mercosur member countries, Fernandez said.