| Willoughby to Somerset (New Jersey) | 368.14 mi (592.47 km) |
| Willoughby to Somersworth (New Hampshire) | 547.45 mi (881.04 km) |
| Willoughby to Somerton (Arizona) | 1,923.56 mi (3,095.68 km) |
| Willoughby to Somerville (Massachusetts) | 531.24 mi (854.95 km) |
| Willoughby to Somerville (New Jersey) | 361.59 mi (581.92 km) |
| Willoughby to Sonoma (California) | 2,165.56 mi (3,485.13 km) |
| Willoughby to Soquel (California) | 2,170.30 mi (3,492.77 km) |
| Willoughby to South Bend (Indiana) | 250.90 mi (403.79 km) |
| Willoughby to South Bradenton (Florida) | 982.31 mi (1,580.88 km) |
| Willoughby to South Burlington (Vermont) | 456.62 mi (734.86 km) |
| Willoughby to South Charleston (West Virginia) | 228.81 mi (368.24 km) |
| Willoughby to South Daytona (Florida) | 862.59 mi (1,388.21 km) |
| Willoughby to South El Monte (California) | 2,050.09 mi (3,299.30 km) |
| Willoughby to South Elgin (Illinois) | 356.26 mi (573.35 km) |
| Willoughby to South Euclid (Ohio) | 10.34 mi (16.64 km) |
