Greatest Series of All TYM!!!!! discussion

These ranks are based on my own favorites. Feel free to comment yours. This is my top 10 (5-10 are not in particular order):
1. The Chronicles of Narnia
2. Harry Potter
3. The Middle Earth Legendarium
4. Prydain Chronicles
5. Time Quartet
6. Percy Jackson and the Olympians
7. Septimus Heap
8. Inheritance Cycle
9. Divergent trilogy
10. Earthsea cycle