| Tulcea to Odessa (Texas) | 6,293.89 mi (10,129.03 km) |
| Tulcea to Ogden (Utah) | 5,992.64 mi (9,644.22 km) |
| Tulcea to Oildale (California) | 6,514.92 mi (10,484.74 km) |
| Tulcea to Ojus (Florida) | 5,803.45 mi (9,339.76 km) |
| Tulcea to Okemos (Michigan) | 5,107.13 mi (8,219.12 km) |
| Tulcea to Oklahoma City (Oklahoma) | 5,934.17 mi (9,550.13 km) |
| Tulcea to Okmulgee (Oklahoma) | 5,877.21 mi (9,458.46 km) |
| Tulcea to Olathe (Kansas) | 5,655.97 mi (9,102.40 km) |
| Tulcea to Old Jamestown (Missouri) | 5,509.64 mi (8,866.90 km) |
| Tulcea to Oldsmar (Florida) | 5,798.10 mi (9,331.14 km) |
| Tulcea to Olean (New York) | 4,926.77 mi (7,928.87 km) |
| Tulcea to Olive Branch (Mississippi) | 5,703.78 mi (9,179.34 km) |
| Tulcea to Olivehurst (California) | 6,330.24 mi (10,187.53 km) |
| Tulcea to Olney (Maryland) | 5,018.82 mi (8,077.01 km) |
| Tulcea to Olympia (Washington) | 5,836.34 mi (9,392.68 km) |
