On 18 June 1971, the biggest engagement between Allied and Communist forces in Phu Yen Province since 1968 transpired in Son Hoa District. During the 1968 Tet Offensive, Communist forces made three failed attempts to capture the province capital of Tuy Hoa City. Three years later, the sounds of impacting mortar rounds and B-40 rockets marked the start of t the People's Liberation Armed Forces (PLAF) attempt at overrunning the Government of Vietnam (GVN) assets at Cung Son. Accomplishing such a feat would effectively evict the GVN from Song Hoa District, thus giving the National Liberation Front (NLF) full control of western Phu Yen. To reach the GVN facilities, enemy forces descended on an area to the northwest of the district. Roughly two kilometers to the northwest to the Song Hoa District Headquarters, sat Hon Ngang, a hill which dominated the terrain around Cung Son. Atop the hill stood Regional Force (RF) Group 53's headquarters and firebase.
