HANOI, Sept. 2 (Xinhua) -- A 139.2-km expressway linking Da Nang city and Quang Ngai province in Vietnam's central region, whose construction cost totaled over 34,516 billion Vietnamese dong (1.5 billion U.S. dollars), opened to traffic on Sunday.

The expressway, which allows vehicles to run at a speed of up to 120 km per hour, helps halve travel time between Da Nang and Quang Ngai to one and a half hours compared with running on national road 1A, said the Transport Ministry.

The expressway, whose construction started in 2013, runs through the three central localities of Da Nang, Quang Nam and Quang Ngai which form part of Vietnam's central key economic zone.

The expressway is also expected to facilitate transport the Vietnam-Laos-Cambodia economic triangle through the West-East Economic Corridor to seaports in Vietnam's central region, said the ministry.?