Regions of Japan
- Ōkawa
- Ōkawa
- Ōkawaotsu
- Ōkawa
- Okatomi
- Ōgasho
- Ōkarōto Yama
- Ōkaramatsu-san
- Takayanagichō-okanomachi
- Ōganeku
- Okamura Jima
- Okamoto Gawa
- Okami Jima
- Ōkamigō Gawa
- Okameno Hana
- Okamachi
- Okake-bana
- Okake
- Ōkaji Zaki
- Okagata-mura
- Okagaki Machi
- Ōkado Hana
- Okada Yama
- Shōinmachi-okata
- Okada
- Okata
- Yamagawa-okachiyogamizu
- Ōgachi
- Okabechō-okabe
- Ōkaba
- Oka
- Ōka
- Miyamaku-aiga
- Oka
- Ōka
- Shimokamagarichō-ōjizō
- Ojiya-shi
- Ojiya
- Oji-shima
- Ojiro-mura
- Ōjimachi
- Ojimachō
- Ō Jima
- Ō-jima
- Ojika Jima
- Ojika-seto
- Ojikano-okino-ishi
- Ojika-gawa
- Ojika Chō
- Ōjigawa-mura
- Ōjiga-shima
- Ojika Se
- Ōji-chō
- Ōji
- Shinochō-ōji
- Ōji
- Ōjana
- Ōja-mine
- Ōizumi-mura
- Ōizumi-machi
- Oizu-machi
- Oizu
- Ōiwa Yama
- Oiwake
- Oiwake
- Oiwake
- Oiwake
- Ōiwa Gawa
- Ō-iwa-dake
- Oizuru Yama
- Oitsu-mura
- Oitsukami-jima
- Oitsu
- Ōita-shi
- Ōita-machi
- Oita-kōtsū-hōshū-sen
- Ōita Kō
- Oita Prefecture
- Ōita-gun
- Ōita Gawa
- Ōita
- Ōi-Suzugamorichō
- Ōiso-saki
- Ōiso-machi
- Ō Iso
- Ōiso
- Ōishi Wan
- Oishino Hana
- Ōishihara-hana
- Oishiga Mine
- Oise Bana
- Oishi
- Ōishi
- Ōishi
- Ōin Zan
- Oino-yama
- Ōinokawa
- Oriono
- Ōihama
- Ōi-mura
- Ōi-Minamihamagawachō
- Ōi Machi
- Ōi Machi
- Higashiōi
- Oike-yama
- Ōike
- Ōike
- Ōi Gawa
- Oikami-mura
- Ōi-Kaiganchō
- Ōi-gun
- Ōi Gawa
- Ōi Gawa
- Oizuruga Take
- Ōie
- Oi Dake
- Ōichō
- Ōi-chō
- Ōi-chō
- Oibana Zaki
- Oiage
- Ōi
- Ōi
- Ōi
- Ōi
- Ōi
- Ōi
- Ōi
- Ōhori
- Ōhori-ike
- Ōbora Yama
- Ōhora-yama
- Ōhito
- Ōhirota
- Ōhira San
- Taihei Zan
- Ōhira Yama
- Ōhira Yama
- Ōhira-yama
- Ōhira Yama
- Ōhira Yama
- Ōhira Se
- Ōhira-mura
- Ōhira-misaki
- Ōhira-machi
- Ōhira
- Ōhinata
- Ōhiki Shima
- Ohida
- Ōhibara Yama
- Ōhata
- Ōha Jima
- Ōhashi Gawa
- Ōharu-chō
- Oharu
- Ōhara
- Ōbaru Saki
- Ōhara-mura
- Ōhara-chō
- Ohara
- Ōhara
- Ō-hana
- O Bana
- Ō-hana
- Ō-hana
- Ohama Misaki
- Ōhama-mura
- Ōhama-chō
- Ōhama-chō
- Ōhama
- Ohama
- Ōhama
- Ōhama
- Ōhama
- Ōhamamachi
- Ōhama
- Hama
- Ōhama
- Ōhama
- Ō-hama
- Ōhama-nakamachi
- Ō-haka-jima
- Ōhaino-hana
- Daihachiga Gawa
- Ōguta
- Ōgusuku Yama
- Ōshiro
- Ōkushi Misaki
- Ogushi Ura
- Ogushi
- Ōguro-yama
- Oguroi
- Ogura Saki
- Ogura San
- Ogura-mura
- Ogura Gawa
- Ogura-gawa
- Ogura
- Ogura
- Oguni Machi