For the La Unión province of El Salvador, see La Unión Department, El Salvador.
Basic Ridge. Located 9 kilometers northeast of San Fernando town proper through the Imperial Army in the province. Later, the Ridge constituted the East Flank of the 121st Infantry of the United States Armed Forces in the Philippines, Northern Luzon (USAFIP NL) during the Liberation in 1945
Ilocano is the common dialect. The residents of the coastal barangay of Sto. Tomas and Rosario also speak Pangasinense while the cultural communities in the towns bordering the Cordillera speak Ibaloi or Kankanacy. English and Filipino remain as basic tools of instruction in schools.