Why do Canadian airports start with Y?

Related questions

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7. Can I just move to Canada?
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Tags

1. #learned
2. #stands
3. #states
4. #which
5. #really
6. #calgary
7. #ottawa
8. #vancouver
9. #vancouverite
10. #canadian
11. #weather
12. #rainy
13. #codes
14. #colodey
15. #after
16. #stations
17. #letters
18. #united
19. #airports