| Gary to Odessa (Texas) | 1,064.86 mi (1,713.73 km) |
| Gary to Ogden (Utah) | 1,271.77 mi (2,046.71 km) |
| Gary to Oildale (California) | 1,754.39 mi (2,823.41 km) |
| Gary to Ojus (Florida) | 1,155.29 mi (1,859.25 km) |
| Gary to Okemos (Michigan) | 168.88 mi (271.78 km) |
| Gary to Oklahoma City (Oklahoma) | 692.66 mi (1,114.73 km) |
| Gary to Okmulgee (Oklahoma) | 623.25 mi (1,003.03 km) |
| Gary to Olathe (Kansas) | 436.07 mi (701.78 km) |
| Gary to Old Jamestown (Missouri) | 245.22 mi (394.65 km) |
| Gary to Oldsmar (Florida) | 971.99 mi (1,564.27 km) |
| Gary to Olean (New York) | 459.98 mi (740.27 km) |
| Gary to Olive Branch (Mississippi) | 477.64 mi (768.68 km) |
| Gary to Olivehurst (California) | 1,798.24 mi (2,893.98 km) |
| Gary to Olney (Maryland) | 566.27 mi (911.32 km) |
| Gary to Olympia (Washington) | 1,781.09 mi (2,866.38 km) |
