| Keystone to Marshall (Minnesota) | 1,341.74 mi (2,159.32 km) |
| Keystone to Marshall (Missouri) | 972.08 mi (1,564.41 km) |
| Keystone to Marshall (Texas) | 763.45 mi (1,228.65 km) |
| Keystone to Marshalltown (Iowa) | 1,121.57 mi (1,805.00 km) |
| Keystone to Marshfield (Wisconsin) | 1,216.02 mi (1,956.99 km) |
| Keystone to Martha Lake (Washington) | 2,512.02 mi (4,042.70 km) |
| Keystone to Martin (Tennessee) | 674.18 mi (1,084.98 km) |
| Keystone to Martinez (California) | 2,367.95 mi (3,810.85 km) |
| Keystone to Martinez (Georgia) | 373.58 mi (601.21 km) |
| Keystone to Martinsburg (West Virginia) | 826.07 mi (1,329.42 km) |
| Keystone to Martinsville (Indiana) | 809.86 mi (1,303.35 km) |
| Keystone to Martinsville (New Jersey) | 974.64 mi (1,568.53 km) |
| Keystone to Martinsville (Virginia) | 611.94 mi (984.82 km) |
| Keystone to Maryland City (Maryland) | 827.58 mi (1,331.86 km) |
| Keystone to Maryland Heights (Missouri) | 860.18 mi (1,384.33 km) |
