| A | B |
|---|
| Atlantic Ocean | highway for explorers and settlers |
| Pacific Ocean | early exploration destination |
| Mississippi River | largest river in North America |
| Ohio River | gateway to the West |
| Missouri River | one of the rivers used to transport farm products |
| Columbia River | explored by Lewis and Clark |
| Colorado River | explored by the Spanish |
| Rio Grande | forms the border with Mexico |
| St. Lawrence River | forms part of the northeastern border with Canada |
| Gulf of Mexico | provided French and Spanish with exploration routes |
| Great Lakes | Huron, Ontario, Michigan, Erie, Superior |
