Estados Unidos
Países do mundo
O
- (Lee County) Oakdale
- (Jenkins County) Old Hundred
- (Crenshaw County) Oaks
- (Russell County) Old Monroe
- (Washington County) Oakford
- (White County) Oakley
- (Franklin County) Old Washington
- (Washington County) Orient
- (Talladega County) Okreek
- (Jenkins County) Otis
- (Madison County) Omena
- (Houston County) Okahumpka
- (Clarke County) Ocotillo
- (Etowah County) Orrstown
- (Greene County) Oil Trough
- (Washington County) Oconee
- (Arkansas County) Oak Hall
- (Lee County) Opdyke
- (Dale County) Ostrander
- (Franklin County) Omaha
- (Coffee County) Oak Ridge
- (Chambers County) Olde West Chester
- (Blount County) Olar
- (Boone County) Oakgrove
- (Macon County) Olds
- (San Jacinto County) Oakhurst
- (Pickens County) Oakland
- (Greene County) Owendale
- (Jenkins County) Oak Grove
- (Chilton County) Owaneco