| Port Huron to Ratingen | 3,970.74 mi (6,390.29 km) |
| Port Huron to Ratzeburg | 4,028.63 mi (6,483.46 km) |
| Port Huron to Raubling | 4,299.21 mi (6,918.92 km) |
| Port Huron to Rauenberg | 4,113.04 mi (6,619.30 km) |
| Port Huron to Raunheim | 4,076.21 mi (6,560.03 km) |
| Port Huron to Ravensburg | 4,203.24 mi (6,764.46 km) |
| Port Huron to Recke | 3,966.23 mi (6,383.03 km) |
| Port Huron to Recklinghausen | 3,972.60 mi (6,393.29 km) |
| Port Huron to Regen | 4,291.97 mi (6,907.26 km) |
| Port Huron to Regensburg | 4,250.67 mi (6,840.80 km) |
| Port Huron to Regenstauf | 4,248.24 mi (6,836.88 km) |
| Port Huron to Rehau | 4,200.99 mi (6,760.85 km) |
| Port Huron to Rehburg-Loccum | 4,017.69 mi (6,465.84 km) |
| Port Huron to Rehlingen-Siersburg | 4,031.53 mi (6,488.12 km) |
| Port Huron to Reichelsheim | 4,101.92 mi (6,601.39 km) |
