| Duncan to Dover (New Hampshire) | 1,563.72 mi (2,516.56 km) |
| Duncan to Dover (New Jersey) | 1,345.19 mi (2,164.87 km) |
| Duncan to Dover (Ohio) | 989.22 mi (1,591.99 km) |
| Duncan to Downers Grove (Illinois) | 734.36 mi (1,181.85 km) |
| Duncan to Downey (California) | 1,153.18 mi (1,855.87 km) |
| Duncan to Dranesville (Virginia) | 1,175.56 mi (1,891.89 km) |
| Duncan to Draper (Utah) | 866.19 mi (1,393.99 km) |
| Duncan to Drexel Heights (Arizona) | 774.92 mi (1,247.11 km) |
| Duncan to Drexel Hill (Pennsylvania) | 1,294.86 mi (2,083.88 km) |
| Duncan to Duarte (California) | 1,140.94 mi (1,836.17 km) |
| Duncan to Dublin (California) | 1,351.99 mi (2,175.82 km) |
| Duncan to Dublin (Georgia) | 873.67 mi (1,406.04 km) |
| Duncan to Dublin (Ohio) | 896.91 mi (1,443.43 km) |
| Duncan to Dubuque (Iowa) | 673.61 mi (1,084.06 km) |
| Duncan to Duluth (Georgia) | 786.61 mi (1,265.92 km) |
