| Mountain Ash to Joliet (Illinois) | 3,853.99 mi (6,202.39 km) |
| Mountain Ash to Jonesboro (Arkansas) | 4,223.50 mi (6,797.07 km) |
| Mountain Ash to Joplin (Missouri) | 4,311.38 mi (6,938.50 km) |
| Mountain Ash to Joppatowne (Maryland) | 3,477.02 mi (5,595.73 km) |
| Mountain Ash to Juana Díaz (Puerto Rico) | 4,101.47 mi (6,600.67 km) |
| Mountain Ash to Junction City (Kansas) | 4,304.36 mi (6,927.19 km) |
| Mountain Ash to Juneau (Alaska) | 4,340.84 mi (6,985.91 km) |
| Mountain Ash to Jupiter (Florida) | 4,227.04 mi (6,802.76 km) |
| Mountain Ash to Jupiter Farms (Florida) | 4,231.43 mi (6,809.83 km) |
| Mountain Ash to Jurupa Valley (California) | 5,304.06 mi (8,536.06 km) |
| Mountain Ash to Justice (Illinois) | 3,831.22 mi (6,165.76 km) |
| Mountain Ash to Kahului (Hawaii) | 7,165.85 mi (11,532.31 km) |
| Mountain Ash to Kailua (Hawaii) | 7,154.64 mi (11,514.28 km) |
| Mountain Ash to Kalamazoo (Michigan) | 3,720.35 mi (5,987.33 km) |
| Mountain Ash to Kalispell (Montana) | 4,426.64 mi (7,123.99 km) |
