Along the Open Road to the DMZ: a military convoy heads along Route One toward the demilitarized zone in South Vietnam from Hue. Route One, the main south-north line of communication between Saigon and the DMZ, is open and passable. During the day, traffic is considered secure between Phan Rang and the DMZ. The only area where Viet Cong roadblocks must be expected is about 60-90 miles northeast of Saigon