| Alpena to Popovo | 4,957.55 mi (7,978.40 km) |
| Alpena to Provadia | 5,007.84 mi (8,059.34 km) |
| Alpena to Radnevo | 4,998.75 mi (8,044.70 km) |
| Alpena to Radomir | 4,878.72 mi (7,851.55 km) |
| Alpena to Rakitovo | 4,947.51 mi (7,962.25 km) |
| Alpena to Rakovski | 4,964.59 mi (7,989.73 km) |
| Alpena to Razgrad | 4,958.44 mi (7,979.84 km) |
| Alpena to Razlog | 4,929.82 mi (7,933.78 km) |
| Alpena to Ruse | 4,924.45 mi (7,925.13 km) |
| Alpena to Samokov | 4,911.10 mi (7,903.65 km) |
| Alpena to Sandanski | 4,938.30 mi (7,947.43 km) |
| Alpena to Sevlievo | 4,933.80 mi (7,940.19 km) |
| Alpena to Shumen | 4,985.41 mi (8,023.23 km) |
| Alpena to Silistra | 4,955.38 mi (7,974.92 km) |
| Alpena to Sliven | 4,994.02 mi (8,037.11 km) |
