Phu Yen is a coastal province in the South Central Coast of Vietnam. It is the easternmost province of Vietnam's mainland. Phu Yen borders Binh Dinh Province to the north, Khanh Hoa Province to the south. Phu Yen is separated from these provinces by two passes: Cu Mong pass in the north and Ca pass in the south. The province's topography consists of hilly regions in the west (70%) and the fertile plain of Tuy Hoa in the east. Lowlands also extend west along Da Rang river. The highest peaks are at 1592m on the border to Khanh Hoa Province in the south and at 1331m in the northwest (Dong Xuan District).