| Napa to Orangevale (California) | 64.34 mi (103.55 km) |
| Napa to Orchards (Washington) | 510.84 mi (822.12 km) |
| Napa to Orcutt (California) | 258.78 mi (416.47 km) |
| Napa to Oregon (Ohio) | 2,053.53 mi (3,304.84 km) |
| Napa to Oregon (Wisconsin) | 1,744.09 mi (2,806.84 km) |
| Napa to Oregon City (Oregon) | 486.94 mi (783.66 km) |
| Napa to Orem (Utah) | 583.07 mi (938.35 km) |
| Napa to Orinda (California) | 29.55 mi (47.55 km) |
| Napa to Orland Park (Illinois) | 1,826.12 mi (2,938.85 km) |
| Napa to Orlando (Florida) | 2,437.06 mi (3,922.07 km) |
| Napa to Ormond Beach (Florida) | 2,424.53 mi (3,901.90 km) |
| Napa to Oro Valley (Arizona) | 755.45 mi (1,215.78 km) |
| Napa to Oroville (California) | 92.06 mi (148.15 km) |
| Napa to Oshkosh (Wisconsin) | 1,785.82 mi (2,873.99 km) |
| Napa to Oskaloosa (Iowa) | 1,580.34 mi (2,543.31 km) |
