Why are there holes in the pantheon?

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Tags

1. #oculus
2. #light
3. #built
4. #drain
5. #rains
6. #being
7. #floor
8. #obviously
9. #holes
10. #sloping
11. #centre
12. #hidden
13. #water
14. #means
15. #elements
16. #inside
17. #gently
18. #source
19. #pantheon