If you have wondered what does this great city tab does .
Well you can check them now.
You get ranks on various types of exploration and expedition that you make.
Check this pic out
This is what it shows when you click on great cities
After the processing you can get the ranks like this.
Now you get the ranks in various fields like military, economic and cultural and from all time span and last week .
So go get your ranks and play more to get ahead in the list.