 The firebase was strategically important because it offered unfettered views for 15 km east to the coast and north into North Vietnam.It was also very vulnerable because it was within range of PAVN artillery north of the DMZ which was largely immune to counter-battery fire.On 27 February 1967, in response to Marine artillery fire into and the area north of the DMZ (Operation Highrise) PAVN mortar, rocket and artillery fire hit Con Thien and Gio Linh.