 He had noted that the manning of the bases and the defensive posture they developed was contrary to the aggressive style of fighting that Marines favor.In early 1969, intelligence reports indicated there had been a large PAVN build-up in the A Shau and Đa Krông Valleys.The A Shau was just 10  km east of the Laotian border and some 34  km long, while the Đa Krông was several kilometers further east and separated by two mountain ranges.