| Clue | Source | Date |
|---|---|---|
| It goes all around the country, for short | The Atlantic | 31 May 2026 |
| Wash. and Tex. both form part of it | ||
| Part of it was a 2016 campaign issue | LA Times Daily | 19 May 2018 |
| Part of it was a 2016 campaign issue | ||
| Part of it was a 2016 campaign issue | ||
| It runs through four Great Lakes | ||
| It runs through four Great Lakes |