| Napa to Odessa (Texas) | 1,209.12 mi (1,945.89 km) |
| Napa to Ogden (Utah) | 584.50 mi (940.65 km) |
| Napa to Oildale (California) | 268.21 mi (431.64 km) |
| Napa to Ojus (Florida) | 2,583.62 mi (4,157.94 km) |
| Napa to Okemos (Michigan) | 1,996.66 mi (3,213.31 km) |
| Napa to Oklahoma City (Oklahoma) | 1,379.55 mi (2,220.17 km) |
| Napa to Okmulgee (Oklahoma) | 1,458.59 mi (2,347.37 km) |
| Napa to Olathe (Kansas) | 1,479.04 mi (2,380.29 km) |
| Napa to Old Jamestown (Missouri) | 1,721.06 mi (2,769.77 km) |
| Napa to Oldsmar (Florida) | 2,378.56 mi (3,827.92 km) |
| Napa to Olean (New York) | 2,304.70 mi (3,709.05 km) |
| Napa to Olive Branch (Mississippi) | 1,804.89 mi (2,904.70 km) |
| Napa to Olivehurst (California) | 67.31 mi (108.33 km) |
| Napa to Olney (Maryland) | 2,413.13 mi (3,883.55 km) |
| Napa to Olympia (Washington) | 604.92 mi (973.52 km) |
