| Rockville to Smyrna (Delaware) | 84.11 mi (135.36 km) |
| Rockville to Smyrna (Georgia) | 544.96 mi (877.03 km) |
| Rockville to Smyrna (Tennessee) | 556.42 mi (895.46 km) |
| Rockville to Snellville (Georgia) | 524.32 mi (843.81 km) |
| Rockville to Snoqualmie (Washington) | 2,287.34 mi (3,681.12 km) |
| Rockville to Snyder (Texas) | 1,395.76 mi (2,246.26 km) |
| Rockville to Socastee (South Carolina) | 386.81 mi (622.51 km) |
| Rockville to Socorro (Texas) | 1,710.25 mi (2,752.38 km) |
| Rockville to Soddy-Daisy (Tennessee) | 514.28 mi (827.65 km) |
| Rockville to Solana Beach (California) | 2,260.92 mi (3,638.60 km) |
| Rockville to Soledad (California) | 2,396.70 mi (3,857.12 km) |
| Rockville to Solon (Ohio) | 276.35 mi (444.73 km) |
| Rockville to Somers Point (New Jersey) | 137.41 mi (221.14 km) |
| Rockville to Somerset (Kentucky) | 428.21 mi (689.14 km) |
| Rockville to Somerset (New Jersey) | 171.88 mi (276.61 km) |
