Across
- 3. System of government where people vote
- 4. Mountain that erupts lava
- 6. Gas humans need to breathe
- 9. Closest planet to the Sun
- 10. Highest mountain in the world
- 11. Ancient triangular structure in Egypt
- 12. Hardest natural substance
- 13. Tool used to find direction
- 14. Ocean between Europe and America
- 17. Largest ocean on Earth
- 18. Largest planet in our solar system
- 19. Playwright who wrote Hamlet
Down
- 1. Capital city of Japan
- 2. Metal used to make many early tools
- 5. Capital city of Australia
- 6. International sporting event held every four years
- 7. Longest river in the world
- 8. Largest hot desert in the world
- 10. Scientist who developed the theory of relativity
- 13. Temperature scale used in the UK
- 15. Large sea wave caused by an earthquake
- 16. Hottest planet in our solar system