List of cities with the letter O 18 letters in the city name. Cities starting with the first letter O 18 letters in the name.
| Name of the city in O 18 letters | Country |
|---|---|
| Ostrów Wielkopolski | City in Poland 18 letters on O |
| Oliveira de azeméis | City in Portugal 18 letters on O |
| Of Aveiro-de-Nazare | City in Portugal 18 letters on O |