O Osaka (Kunigami-gun) Okinawa Okayama Okazaki Odawara Oyama Obihiro (Okinawa Shi) Okinawa Otaru Onomichi Okegawa Okaya Ono (Nishisonogi-gun) Obita (Sanyōonoda Shi) Onoda (Katō-gun) Otofuke Ō Ōita Ōtsu Ōta Ōgaki Ōmuta Ōme Ōmura Ōbu Ōdate (Ōtawara-shi) Ōtawara (Sambu-gun) Ōami (Fujimino Shi) Ōi (Ōzu-shi) Ōzu (Daisen-shi) Ōmagari