Royaume-Uni
Villes commençant par o
- Oadby
- Oakengates
- Oakham
- Oakhanger
- Oakhill
- Oakington
- Oakley
- Oakley
- Oakley
- Oaksey
- Oare
- Oban
- Occold
- Ochiltree
- Odcombe
- Odiham
- Offham
- Offwell
- Ogmore-by-Sea
- Ogmore Vale
- Okehampton
- Old Basing
- Old Bolingbroke
- Old Buckenham
- Old Dalby
- Old Harlow
- Old Kilpatrick
- Old Leake
- Old Newton
- Old Sarum
- Old Windsor
- Oldbury
- Oldbury-on-Severn
- Oldham
- Oldmeldrum
- Olney
- Olveston
- Omagh
- Ombersley
- Orcheston
- Orford
- Orleton
- Orlingbury
- Ormesby St Margaret
- Ormiston
- Ormskirk
- Orpington
- Orsett
- Orston
- Orton