| Duncan to Glen Carbon (Illinois) | 527.50 mi (848.92 km) |
| Duncan to Glen Cove (New York) | 1,392.74 mi (2,241.40 km) |
| Duncan to Glen Ellyn (Illinois) | 735.75 mi (1,184.07 km) |
| Duncan to Glen Rock (New Jersey) | 1,368.45 mi (2,202.30 km) |
| Duncan to Glendale (Arizona) | 821.09 mi (1,321.41 km) |
| Duncan to Glendale (California) | 1,157.59 mi (1,862.95 km) |
| Duncan to Glendale (Wisconsin) | 799.69 mi (1,286.98 km) |
| Duncan to Glendale Heights (Illinois) | 737.51 mi (1,186.91 km) |
| Duncan to Glendora (California) | 1,135.19 mi (1,826.92 km) |
| Duncan to Glenmont (Maryland) | 1,193.46 mi (1,920.68 km) |
| Duncan to Glenn Dale (Maryland) | 1,205.47 mi (1,940.01 km) |
| Duncan to Glenn Heights (Texas) | 150.60 mi (242.37 km) |
| Duncan to Glenpool (Oklahoma) | 145.45 mi (234.08 km) |
| Duncan to Glens Falls (New York) | 1,431.73 mi (2,304.15 km) |
| Duncan to Glenvar Heights (Florida) | 1,213.58 mi (1,953.06 km) |
