Oslo
Oruro is a city in Bolivia
Oak Park is a city in Michigan. It begins with the letter O.
Ordos is a city in Inner Mongolia, China.
Odessa
There are no cities in Greece that begin with the letter O. Oia is a small town in Greece.
Orangeburg, South Carolina
Baltimore Orioles. Orlando Magic. Oklahoma City Thunder. Oakland A's.
Ozark is a city in Arkansas
O'Fallon is a city in St. Clair County, Illinois.
Olney and O'Donnell
Olympia WA, Oklahoma City OK, Omaha NE, Ogden UT, Orlando FL and Oakland CA are U.S. cities. They begin with the letter O.