| Grayslake to Orangevale (California) | 1,750.12 mi (2,816.54 km) |
| Grayslake to Orchards (Washington) | 1,716.14 mi (2,761.87 km) |
| Grayslake to Orcutt (California) | 1,811.05 mi (2,914.60 km) |
| Grayslake to Oregon (Ohio) | 241.00 mi (387.85 km) |
| Grayslake to Oregon (Wisconsin) | 79.87 mi (128.54 km) |
| Grayslake to Oregon City (Oregon) | 1,721.26 mi (2,770.11 km) |
| Grayslake to Orem (Utah) | 1,232.11 mi (1,982.88 km) |
| Grayslake to Orinda (California) | 1,817.90 mi (2,925.62 km) |
| Grayslake to Orland Park (Illinois) | 51.41 mi (82.74 km) |
| Grayslake to Orlando (Florida) | 1,028.54 mi (1,655.28 km) |
| Grayslake to Ormond Beach (Florida) | 980.37 mi (1,577.75 km) |
| Grayslake to Oro Valley (Arizona) | 1,427.45 mi (2,297.26 km) |
| Grayslake to Oroville (California) | 1,750.07 mi (2,816.47 km) |
| Grayslake to Oshkosh (Wisconsin) | 119.23 mi (191.89 km) |
| Grayslake to Oskaloosa (Iowa) | 247.99 mi (399.10 km) |
