 Ordered to secure a base of operations for itself and the remainder of the 25th Infantry Division in the vicinity of the town Tan An Hoi in the Cu Chi District of Vietnam, the Brigade Task Force embarked on 66 days of continuous combat operations in a completely Viet Cong dominated, heavily entrenched and fiercely defended area.On January 1966, combat operations began to seize, clear and secure the area selected for a base of operations.For the initial four days, brigade combat elements moved forward against devastating automatic weapons and continual harassing sniper fire, well established mine fields and vast underground systems of tunnels, trenches, spider holes and fortifications unrivaled in Vietnam.