What purpose did Machu Picchu serve?

Related questions

1. Why was Machu Picchu not destroyed?
2. How much should I budget for a trip to Peru?
3. Why did Machu Picchu take so long?
4. How old is Machu Picchu?
5. Why is Machu Picchu a mystery?
6. Should I hike Angels Landing?
7. How long is the Inca Trail in miles?
8. What's so special about Machu Picchu?
9. How much do you tip in Peru?
10. What is the best time of year to visit Machu Picchu?

Tags

1. #estate
2. #marking
3. #purpose
4. #sanctuary
5. #picchu
6. #royal
7. #religious
8. #machu
9. #style
10. #sacred
11. #place
12. #retreat
13. #popularized
14. #built
15. #multi
16. #emperor
17. #pachacuti
18. #court