Regions of Japan
- Ōtsu-hana
- Ōtsu-hana
- Ōtsuchi-wan
- Ōtsuchi-gawa
- Ōtsuchi-chō
- Ōtsuchi
- Otsuai
- Ōtsu
- Ōtsu
- Otōtojima Seto
- Otōto Jima
- Ōdori
- Kamiotonashi
- Otomo-ura
- Otomomachi
- Otomo-gawa
- Otomo
- Otobe
- Ote-mura
- Ōtawara-shi
- Ōtawara
- Ōtama Mura
- Ōta-machi
- Ōtakine Yama
- Ōtakine Gawa
- Ōtaki
- Ōdaki
- Ōtaki
- Ōtaka-mori
- Ōta Gawa
- Ōta
- Tsukidate-ōta
- Ōta
- Ōsu Zaki
- Osuke Yama
- Ogatsuchō-ōsu
- Oshō-yama
- Ōshio-misaki
- Ōshio Mura
- Ōshima Seto
- Ō-shima
- Ō-shima
- Ō Shima
- Ō Shima
- Oshika Hantō
- Oshika Chō
- Ōse
- Ōsawa-yama
- Ōsawa-mura
- Ōsawagōshuku
- Ōsawa-gawa
- Ōsawa-gawa
- Ōsawa
- Ōsawa
- Ōsato Chō
- Ōsashi-saki
- Ōsasa-yama
- Osaki Misaki
- O-zaki
- Osabe Gyokō
- Kamiosabe
- Oritate
- Orikasa-kawa
- Oppa Wan
- Kitakami Gawa
- Oppa
- Ōnuma-mura
- Tajiri-ōnuki
- Ōno Wan
- Ono-niimachi
- Ononii-machi
- Ōno-mura
- Onogawa-mura
- Onogawa Ko
- Onogawa
- Onoda-machi
- Ono
- Ōno
- Onjuku Machi
- Gojōmori Yama
- Oniyanagi-mura
- Oniyanagichō
- Ōne-zaki
- Ōne-saki
- Ō-ne
- Ō-ne
- Ondoko-yama
- Ōnakajima
- Ō-naka
- Onahama-wan
- Onahama-machi
- Onahama-kō
- Onahama
- Onahama
- Onagawa Wan
- Onagawa Kō
- Onagawa Chō
- Ōnabakari
- Ōmuro Zaki
- Ōmura-machi
- Okumura
- Omoto-gawa
- Omoto
- Omotegō-mura
- Omoshiro Yama
- Ōmori-yama
- Ōmori Yama
- Ōmori Yama
- Ōmori Yama
- Ōmori-yama
- Ōmori Jima
- Ōmori
- Ōmori
- Ōmori
- Omono-gawa
- Omono Gawa
- Omoe
- Onmae Wan
- Onmaehama
- Ōmiya-machi
- Ōmiya
- Ōmine-yama
- Ōmika
- Omigawa-machi
- Omigawa
- Omi
- Ombi-yama
- Ōmata-yama
- Ōmaemi Jima
- Ōmagari-shi
- Ōmagari
- Ōmagari
- Ōmachi
- Oku Yama
- Ōkura Gawa
- Okunoyahama
- Okunoya
- Okunoya
- Ōkuma-mura
- Ōkuma Machi
- Ōkubo
- Ōkubo
- Ōkubo
- Ōkubo
- Okoma Yama
- Okirai-wan
- Okirai Peninsula
- Okitsu Kō
- Okitsu
- Okitama-gun
- Ōkita-gawa
- Okita
- Oki-sannō-jima
- Okina Jima
- Okikajikake Ne
- Motochi
- Ōkawara
- Ō-kawa
- Ō Kawa
- Ōkawa
- Ōkaizaki
- Okada
- Ōkabura Yama
- Ōjōji-hara
- Ojima
- Oiwake
- Ōishida
- Ōishi
- Ōisawa-tōge
- Ōire Zaki
- Minamikatamachi-oinogake
- Oinokawara
- HIgashiyuri-oikata
- Oide-zaki
- Ōhori
- Ōho-machi
- Ōhisa Gawa
- Ōhira-mura
- Ōhinata Yama
- Ōhayashi
- Ōhashi
- Ōhashi
- Ōhazama Machi
- Ōhasama
- Ōhari-mura
- Ōhara Wan
- Ōhara-Ōashi
- Ōhara Mura
- Ōhara
- Ōharahama
- Ōhara
- Ohama-hana
- Ogatsuchō-ōhama
- Ohako-zaki
- Ohako-ne
- Ōhachimori-yama
- Ōguromori Yama
- Ōguro-mori
- Oguri
- Oguni Gawa