| Ober Hersdorf | DüTr |
| Ober Kostenz | NeBi |
| Oberbipp | AvAu |
| Oberdiebach | KoBi, NeBi |
| Oberdorf | AvAu |
| Oberhausbergen | MeSt |
| Oberhoffen-sur-Moder | BiSt |
| Obernai | BaSt* |
| Oberschaeffolsheim | MeSt |
| Oberstedem | DüTr |
| Oberstinzel | MeSt |
| Oberwesel | KoBi |
| Oberwil bei Büren | AvAu |
| Occey | LaCh |
| Ochey | SoTo |
| Ochten | LeNi |
| Ockenburg | LeNi |
| Odos | LeBe |
| Odratzheim | MeSt |
| Oedenbourg | StKe |
| Oedenburg | StKe |
| Oeffelt | NiTo |
| Oegstgeest | KaLe |
| Oetrange | TrMe |
| Oeudeghien | ToBa |
| Oeyregave | BeDa |
| Oeyreluy | BeDa |
| Ognon | SeSo |
| Ohnenheim | StKe |
| Oiartzun | H7.3 |
| Oinville-St.-Liphard | OrPa |
| Oirsbeek | XaHe |
| Oiselay-et-Grachaux | LaBe |
| Oisseau-le-Petit | AlMa |
| Oissel | RoEv |
| Olby | MoCl |
| Olhat | ClVo |
| Olk | DüTr |
| Ollières | MuAi |
| Ollioules | FrMa |
| Oloron-Ste.-Marie | SoLe |
| Ombret-Rawsa | MoMa |
| Onesse-et-Laharie | BoDa |
| Onet-le-Château | CaRo, RoJa* |
| Onex | GeMâ |
| Onhaye | MoMa |
| Onnezies | ToBa |
| Onsdorf | TrMe |
| Onzain | ToOr |
| Ooij | HeNi |
| Oos | DüTr |
| Oosterhout | LeNi |
| Oostvlietpolder | LeNi |
| Oostvoorne | H2.1, LeNi |
| Opdehoven | HeKö |
| Opheusden | LeHe, LeNi |
| Ophoven | NiTo |
| Opijnen | LeNi |
| Oppède | RéGa |
| Oppenheim | H6.4, BiSt |
| Oradour-sur-Glane | SaLi |
| Orainville | BaRe |
| Orange | H4.3, AvVa |
| Orbe | PoAv, PoLa |
| Orbec | LiDr, LiEv |
| Orbessan | AuBe |
| Orbigny | H8.1 |
| Orbigny-au-Mont | LaSo |
| Orbigny-au-Val | LaSo |
| Orchamps | ChBe |
| Orchies | ArTo |
| Orcines | MoCl |
| Orgères-en-Beauce | ChBl, ChOr |
| Orgon | RéGa |
| Orival | RoEv |
| Orléans | H4.3, H7.1, H8.1, H8.2, BoAu, ChAn, ChOr, DrPa, OrDe, OrPa, OrSe, |
| ToOr, knooppunt | |
| Ormes | SoRe |
| Ormoy-la-Rivière | OrPa |
| Ornézan | AuBe |
| Orrouy | SeSo |
| Ortrang | DüTr |
| Orval | BoCu |
| Orvault | CoNa |
| Osann-Monzel | NeKo |
| Osmery | BoDe |
| Osny | MaPa |
| Ossey-les-Trois-Maisons | NoTr |
| Ostheim | BaSt* |
| Osthofen | BiSt |
| Ostricourt | ArTo |
| Otterstadt | BiSt |
| Ottmarsheim | StKe |
| Ouanne | BoAu |
| Ouarville | ChAn |
| Ouchy | LaVe |
| Oud Alblas | LeNi |
| Oud Beijerland | LeNi |
| Oud Empel | LeNi |
| Oud Wulven | LeHe |
| Oudalle | HaLi |
| Oudenrijn | LeHe |
| Oudler | WiDü |
| Oudon | NaAn |
| Oulches | PoAr |
| Oullins | LyVi |
| Ourouer-lès-Bourdelins | BoDe, Bourges |
| Ousse | LeBe |
| Outremécourt | LaSo |
| Ouveillan | NaBé |
| Ouve-Wirquin | BoTh |
| Ouzouer-sur-Loire | OrDe |
| Ouzouer-sur-Trézée | OrDe |
| Overasselt | NiTo |
| Ovillers-la-Boisselle | CaAm |
| Oyarzun | H7.3 |
| Oytier-St.-Oblas | ViAo |
| Oze | VaGa |
| Ozoir-le-Breuil | ChBl |