| Diamond Bar to Oswego (Illinois) | 1,684.16 mi (2,710.40 km) |
| Diamond Bar to Oswego (New York) | 2,295.00 mi (3,693.44 km) |
| Diamond Bar to Otsego (Minnesota) | 1,495.74 mi (2,407.16 km) |
| Diamond Bar to Ottawa (Illinois) | 1,655.79 mi (2,664.73 km) |
| Diamond Bar to Ottawa (Kansas) | 1,291.79 mi (2,078.93 km) |
| Diamond Bar to Ottumwa (Iowa) | 1,467.77 mi (2,362.14 km) |
| Diamond Bar to Overland (Missouri) | 1,555.35 mi (2,503.09 km) |
| Diamond Bar to Overland Park (Kansas) | 1,325.17 mi (2,132.66 km) |
| Diamond Bar to Overlea (Maryland) | 2,297.98 mi (3,698.23 km) |
| Diamond Bar to Oviedo (Florida) | 2,181.35 mi (3,510.54 km) |
| Diamond Bar to Owasso (Oklahoma) | 1,249.41 mi (2,010.73 km) |
| Diamond Bar to Owatonna (Minnesota) | 1,484.10 mi (2,388.43 km) |
| Diamond Bar to Owensboro (Kentucky) | 1,730.25 mi (2,784.57 km) |
| Diamond Bar to Owings Mills (Maryland) | 2,283.17 mi (3,674.41 km) |
| Diamond Bar to Owosso (Michigan) | 1,907.42 mi (3,069.69 km) |
