| Walnut Creek to Orangeburg (South Carolina) | 2,311.47 mi (3,719.96 km) |
| Walnut Creek to Orangevale (California) | 70.14 mi (112.88 km) |
| Walnut Creek to Orchards (Washington) | 538.59 mi (866.78 km) |
| Walnut Creek to Orcutt (California) | 228.07 mi (367.04 km) |
| Walnut Creek to Oregon (Ohio) | 2,049.14 mi (3,297.77 km) |
| Walnut Creek to Oregon (Wisconsin) | 1,740.88 mi (2,801.68 km) |
| Walnut Creek to Oregon City (Oregon) | 514.80 mi (828.49 km) |
| Walnut Creek to Orem (Utah) | 578.23 mi (930.57 km) |
| Walnut Creek to Orinda (California) | 7.73 mi (12.44 km) |
| Walnut Creek to Orland Park (Illinois) | 1,821.35 mi (2,931.17 km) |
| Walnut Creek to Orlando (Florida) | 2,421.23 mi (3,896.59 km) |
| Walnut Creek to Ormond Beach (Florida) | 2,409.36 mi (3,877.49 km) |
| Walnut Creek to Oro Valley (Arizona) | 729.94 mi (1,174.73 km) |
| Walnut Creek to Oroville (California) | 113.33 mi (182.38 km) |
| Walnut Creek to Oshkosh (Wisconsin) | 1,783.96 mi (2,871.01 km) |
