| Castel Gandolfo to Silver Firs (Washington) | 5,658.20 mi (9,105.99 km) |
| Castel Gandolfo to Silver Spring (Maryland) | 4,492.17 mi (7,229.44 km) |
| Castel Gandolfo to Silver Springs Shores (Florida) | 5,132.33 mi (8,259.69 km) |
| Castel Gandolfo to Silverdale (Washington) | 5,682.91 mi (9,145.76 km) |
| Castel Gandolfo to Silverton (Oregon) | 5,841.70 mi (9,401.31 km) |
| Castel Gandolfo to Simi Valley (California) | 6,348.56 mi (10,217.01 km) |
| Castel Gandolfo to Simpsonville (South Carolina) | 4,900.24 mi (7,886.17 km) |
| Castel Gandolfo to Sioux City (Iowa) | 5,134.79 mi (8,263.64 km) |
| Castel Gandolfo to Sioux Falls (South Dakota) | 5,098.33 mi (8,204.98 km) |
| Castel Gandolfo to Skokie (Illinois) | 4,820.22 mi (7,757.39 km) |
| Castel Gandolfo to Sleepy Hollow (New York) | 4,273.60 mi (6,877.69 km) |
| Castel Gandolfo to Slidell (Louisiana) | 5,432.99 mi (8,743.56 km) |
| Castel Gandolfo to Smithfield (North Carolina) | 4,691.68 mi (7,550.52 km) |
| Castel Gandolfo to Smithfield (Utah) | 5,704.62 mi (9,180.69 km) |
| Castel Gandolfo to Smithville (Missouri) | 5,210.75 mi (8,385.89 km) |
