What where the majors battle of the Vietnam War?

I'm not sure, but the Battle of Ia Drang Valley has got to be right up there near the top. November 1968 450 men were dropped into a small clearing. They were immediately surrounded by 2,000 North Vietanmese soldiers. Three days later and only 2 1/2 miles away a sister battalion was massacred. Read "We Were Soldiers Once...And Young"