| A | B |
|---|
| Columbia River | In the Northwest, explored by Lewis and Clark. |
| Ohio River | Gateway to the West, east of the Mississippi River. |
| Gulf of Mexico | Allowed the Spanish and French access to the Southwest. |
| Colorado River | Explored by the Spanish, in the Southwest. |
| Mississippi River | The river that runs across the United States and empties into the Gulf of Mexico. It has two tributaries (branches) coming off of it and provided transportation for farm and industrial products. |
| Missouri River | WEst of the mississippi River. Provided transportation of farm and industrial products. |
| Pacific Ocean | An early exploration destination. |
| Atlantic Ocean | Watery highway to North America from Europe provided a route to America for explorers, early settlers and later immigrants. |
| St. Lawrence River | Connects the Atlantic Ocean to the Great Lakes (Lake Ontario). |
| Rio Grande River | A natural border between Mexico and the United States. |
