| Answer | Crossword Clue |
|---|---|
| DESOTO | First European to cross the Mississippi |
| DESOTO | First European to see the Mississippi |
| ALONSO | Explorer ... Álvarez de Pineda, first European to see the Mississippi |
| BALBOA | First European to cross America |
| GOBIDESERT | Marco Polo was first European to cross it. |
| DESOTO | First white man to see the Mississippi. |
| EADS | ... Bridge, first to span the Mississippi at St. Louis |
| HOOVERDATUM | "The first occupant of the White House to be born west of the Mississippi River," e.g.? |
