Plain of Jars
During the June 1969 rainy season, the Pathet Lao and two North Vietnamese battalions, using Soviet tanks, pushed the Royal Lao Army and the Neutralists out of their base at Muang Sua northwest of the Plain of Jars. Fighting continued during the monsoon season. In September 1969, Vang Pao's Hmong, supported by United States bombing, launched a series of surprise attacks against key points on the Plain of Jars. A new North Vietnamese army division joined the battle shortly thereafter and by February, 1970, had regained all of the devastated plain.