| Duncan to Reidsville (North Carolina) | 1,033.19 mi (1,662.76 km) |
| Duncan to Reisterstown (Maryland) | 1,209.99 mi (1,947.30 km) |
| Duncan to Rendon (Texas) | 141.20 mi (227.24 km) |
| Duncan to Reno (Nevada) | 1,254.15 mi (2,018.37 km) |
| Duncan to Renton (Washington) | 1,538.70 mi (2,476.30 km) |
| Duncan to Republic (Missouri) | 308.57 mi (496.60 km) |
| Duncan to Reston (Virginia) | 1,176.32 mi (1,893.10 km) |
| Duncan to Revere (Massachusetts) | 1,546.30 mi (2,488.52 km) |
| Duncan to Rexburg (Idaho) | 978.99 mi (1,575.54 km) |
| Duncan to Reynoldsburg (Ohio) | 910.73 mi (1,465.68 km) |
| Duncan to Rialto (California) | 1,109.46 mi (1,785.50 km) |
| Duncan to Richardson (Texas) | 128.85 mi (207.37 km) |
| Duncan to Richfield (Minnesota) | 755.14 mi (1,215.27 km) |
| Duncan to Richfield (Wisconsin) | 793.89 mi (1,277.65 km) |
| Duncan to Richland (Washington) | 1,379.15 mi (2,219.53 km) |
