 The main effort of the campaign in Binh Dinh would come on the Bong Son Plain and in the mountains and valleys that bordered it.The plain, a narrow strip of land starting just north of the town of
Bồng Sơn, ran northward along the coast into I Corps.Rarely more than 25 km wide, it consisted of a series of small deltas, which often backed into gently rolling terraces some 30-90m in height, and, at irregular intervals, of a number of mountainous spurs from the highlands.