Walking in Downtown

Chicago series : Walking in downtown
Chicago is such a big town and very well organized. I am surprised that there are a lot of buildings in downtown (both existing buildings and some are being built) but I have seen not many people in the Chicago downtown comparing to how many tall buildings in downtown. On the last photo in this post, I can not remember what the monument name is. Please help me out.

Have a nice day
DSM
Keep Learning/Taking Photos