| The Border States | In the middle State | Also Borders these States |
| Texas and Tennessee | |
| Maryland and Tennessee | |
| California and Colorado | |
| Oregon and Idaho | |
| Indiana and Tennessee | |
| Montana and Nebraska | |
| Michigan and Iowa | |
| New York and Massachusetts | |
| | The Border States | In the middle State | Also Borders these States |
| New Mexico and Arkansas | |
| Mississippi and Florida | |
| Wisconsin and Kentucky | |
| Montana and Iowa | |
| Oklahoma and Arizona | |
| Kentucky and Pennsylvania | |
| Arizona and Oregon | |
|