To honor its 50th anniversary, look back at some of the most striking photos from the United States' longest war in history ... from the fallen city of Da Nang, Vietnam. It took eight hours ...

But Da Nang is also known for having one of the highest contaminations of dioxin from the use of Agent Orange by US forces during the Vietnam war. Dioxin is one of the most highly toxic pollutants.

For nearly 20 years, the Vietnam War waged on ... a role in highlighting the true horrors of the war. Often referred to as “Napalm Girl,” Ut’s horrifying image captured 9-year-old Kim ...

I knew I'd made a friend in Kim, a Vietnamese tourist, when she captured our mutual crush on Da Nang ... the first combat troops of the Vietnam War here, that magical trifecta dazzled military ...

This combination of photos shows members of the 9th U.S. Marine Expeditionary Force, going ashore at Da Nang, South Vietnam, March 8, 1965, top, and a boy playing at the same location on March ...