| Rockville to Portage (Indiana) | 555.16 mi (893.44 km) |
| Rockville to Portage (Michigan) | 491.57 mi (791.11 km) |
| Rockville to Portage (Wisconsin) | 708.48 mi (1,140.19 km) |
| Rockville to Portales (New Mexico) | 1,486.26 mi (2,391.91 km) |
| Rockville to Porterville (California) | 2,282.54 mi (3,673.39 km) |
| Rockville to Portland (Maine) | 477.30 mi (768.14 km) |
| Rockville to Portland (Oregon) | 2,334.67 mi (3,757.28 km) |
| Rockville to Portland (Tennessee) | 539.10 mi (867.60 km) |
| Rockville to Portland (Texas) | 1,390.91 mi (2,238.45 km) |
| Rockville to Portsmouth (New Hampshire) | 430.60 mi (692.98 km) |
| Rockville to Portsmouth (Ohio) | 311.99 mi (502.10 km) |
| Rockville to Portsmouth (Virginia) | 160.58 mi (258.43 km) |
| Rockville to Post Falls (Idaho) | 2,059.07 mi (3,313.76 km) |
| Rockville to Potomac (Maryland) | 5.23 mi (8.41 km) |
| Rockville to Potomac Park (California) | 2,294.32 mi (3,692.36 km) |
