Battle of Hamburger Hill the steeply-sloped hill against well entrenched troops. Attacks were repeatedly repelled by the PAVN defenses. Bad weather also hindered operations. Nevertheless, the Airborne troops took the hill through direct assault, causing extensive casualties to the PAVN forces. The battle took place on Dong Ap Bia (Ap Bia Mountain, ) in the rugged, jungle-shrouded mountains of South Vietnam, from the Laotian border. Rising from the floor of the western A Sầu Valley, Ap Bia Mountain is a solitary massif, unconnected to the ridges of the surrounding Annamite range. It dominates the northern valley, towering some above sea level. Snaking down from
Battle of Catirai fortress on a hill in the area in a difficult position on steep wooded slopes. Despite the warnings of Lorenzo Bernal del Mercado who had reconnoitered the position, Spaniards new to Chile and the Arauco War prevailed on Governor Saravia to order Martín Ruiz de Gamboa to take his command and attack the place. Meanwhile, Llanganabal had gathered all his army there at their fortress to resist the attack. Gamboa's force was badly defeated while attempting to attack up the steep thickly wooded hill into Llanganabal's fortified position. Battle of Catirai The Battle of Catirai took place on January 7,