Quang Tri province
The Ben Hai River traverses the northern reaches of Quang Tri province, marking Vietnam's 17th parallel, which was used as the demarcation line between North and South Vietnam in 1954. The demarcation was intended as a temporary line between the north and south until the elections, to be held in 1956 would reunify the country.
The elections never took place and Quang Tri saw some of the heaviest fighting in all of Vietnam. By the end of the war, the entire province had been more or less flattened and most of the population had been evacuated. Both Quang Tri town and Dong Ha were totally destroyed -- not a building was left standing in either town, and of the 3,000+ villages that once were dotted over the province, eleven remained.
Given this history, the main "attraction" in Quang Tri province is the legacy of this extreme violence. While many choose to visit the DMZ on an organised tour out of Hue, there is no reason why you can't use Dong Ha as a base instead -- there's no shortage of motorcycle-borne guides and you'll most likely avoid the more packaged feel of the trips out of Hue.
Most tours (regardless of starting point) will cover the remnants of the US base at Khe Sanh, the large military cemetery, Camp Carroll and the Rockpile, though individual itineraries can vary a little. North of the Ben Hai River are the Vinh Moc tunnels, similar to the Cu Chi tunnels near Saigon, but far more interesting, less circus-like and a far tighter fit.
