| Keystone to Mendota Heights (Minnesota) | 1,294.31 mi (2,082.99 km) |
| Keystone to Menifee (California) | 2,075.92 mi (3,340.88 km) |
| Keystone to Menlo Park (California) | 2,367.92 mi (3,810.81 km) |
| Keystone to Menomonee Falls (Wisconsin) | 1,082.30 mi (1,741.79 km) |
| Keystone to Menomonie (Wisconsin) | 1,265.95 mi (2,037.34 km) |
| Keystone to Mentor (Ohio) | 939.47 mi (1,511.94 km) |
| Keystone to Mequon (Wisconsin) | 1,085.81 mi (1,747.45 km) |
| Keystone to Merced (California) | 2,274.59 mi (3,660.59 km) |
| Keystone to Mercedes (Texas) | 950.71 mi (1,530.02 km) |
| Keystone to Mercer Island (Washington) | 2,505.90 mi (4,032.85 km) |
| Keystone to Mercerville (New Jersey) | 949.68 mi (1,528.36 km) |
| Keystone to Meriden (Connecticut) | 1,078.63 mi (1,735.88 km) |
| Keystone to Meridian (Idaho) | 2,152.24 mi (3,463.69 km) |
| Keystone to Meridian (Mississippi) | 467.22 mi (751.92 km) |
| Keystone to Merriam (Kansas) | 1,023.02 mi (1,646.40 km) |
