| Diamond Bar to Popovo | 6,631.56 mi (10,672.47 km) |
| Diamond Bar to Provadia | 6,670.78 mi (10,735.59 km) |
| Diamond Bar to Radnevo | 6,687.27 mi (10,762.12 km) |
| Diamond Bar to Radomir | 6,594.77 mi (10,613.25 km) |
| Diamond Bar to Rakitovo | 6,658.37 mi (10,715.61 km) |
| Diamond Bar to Rakovski | 6,663.27 mi (10,723.50 km) |
| Diamond Bar to Razgrad | 6,627.44 mi (10,665.83 km) |
| Diamond Bar to Razlog | 6,647.86 mi (10,698.69 km) |
| Diamond Bar to Ruse | 6,596.22 mi (10,615.59 km) |
| Diamond Bar to Samokov | 6,623.46 mi (10,659.43 km) |
| Diamond Bar to Sandanski | 6,661.45 mi (10,720.57 km) |
| Diamond Bar to Sevlievo | 6,623.04 mi (10,658.76 km) |
| Diamond Bar to Shumen | 6,652.67 mi (10,706.44 km) |
| Diamond Bar to Silistra | 6,609.93 mi (10,637.66 km) |
| Diamond Bar to Sliven | 6,674.21 mi (10,741.10 km) |
