| Rancho Cucamonga to Popovo | 6,617.59 mi (10,649.98 km) |
| Rancho Cucamonga to Provadia | 6,656.92 mi (10,713.28 km) |
| Rancho Cucamonga to Radnevo | 6,673.18 mi (10,739.45 km) |
| Rancho Cucamonga to Radomir | 6,580.41 mi (10,590.15 km) |
| Rancho Cucamonga to Rakitovo | 6,644.08 mi (10,692.61 km) |
| Rancho Cucamonga to Rakovski | 6,649.09 mi (10,700.68 km) |
| Rancho Cucamonga to Razgrad | 6,613.51 mi (10,643.42 km) |
| Rancho Cucamonga to Razlog | 6,633.50 mi (10,675.58 km) |
| Rancho Cucamonga to Ruse | 6,582.26 mi (10,593.12 km) |
| Rancho Cucamonga to Samokov | 6,609.14 mi (10,636.39 km) |
| Rancho Cucamonga to Sandanski | 6,647.05 mi (10,697.39 km) |
| Rancho Cucamonga to Sevlievo | 6,608.94 mi (10,636.05 km) |
| Rancho Cucamonga to Shumen | 6,638.77 mi (10,684.06 km) |
| Rancho Cucamonga to Silistra | 6,596.13 mi (10,615.44 km) |
| Rancho Cucamonga to Sliven | 6,660.20 mi (10,718.55 km) |
