With a total length of 13.4km, the tunnel project extends from Hoa Xuan commune in Phu Yen Province’s Dong Hoa District and ends in Khanh Hoa Province’s Van Tho Commune in Van Ninh District.

This build-operate-transfer (BOT) project is expected to cost VND15.6 trillion (nearly US$760 million) and meet highway standards, with a maximum allowable driving speed of 80kph.

Construction Vice Minister Le Manh Hung said the section of National Highway 1 referred to was through difficult terrain with a winding road and major safety issues such as rubble and landslides.

Hung said the construction of the Deo Ca tunnel was aimed at reducing traffic accidents and increasing the efficiency of National Highway 1. He said it would help boost socio-economic development and better serve the purposes of defence and security in central and highland provinces.