Across
- 2. network of highways across the United States
- 5. of cities and city populations
- 7. who moves from place to place
- 10. located outside a city
- 12. crops and raising animals for food
- 13. Purchase
- 16. Railroad
- 17. land bridge connecting Asia and North America
- 19. of plants, animals, and diseases between the Old and New Worlds
- 20. when the economy becomes weaker
- 23. Democracy
- 24. Lawrence Seaway
Down
- 1. of government that carries out laws
- 2. of people from one place to another
- 3. where people elect leaders to represent them
- 4. water to crops through channels
- 6. Exchange
- 8. of a canal that raises or lowers ships
- 9. that crosses a continent
- 11. waterway used for transportation
- 14. Highway System
- 15. route connecting the Great Lakes to the Atlantic Ocean
- 18. the U.S. bought from France in 1803
- 19. Branch
- 21. land where people moved to settle
- 22. of factories and industry
