O Osan (Boryeong-si) Oiyonu Group (Yeosu-si) Odong Sŏ (Goheung-gun) Odong-do (Boryeong-si) Oehoenggyŏn-do (Ongjin-gun) Obeto (Boryeong-si) O-do Ŏ (Gunsan-si) Ŏch’ŏngdo-ri (Boryeong-si) Ŏeyŏndo