I have been always wanted to see peacock dancing with its feathers open fully. Finally dream come true when we visited Brookfield zoo, Chicago IL.
Brookfield zoo has some free days in every year. During that time it is open and free for all IL residents. PS: There is a 15$ parking fee.
Pro tip: Brookfield zoo is very big. I would take a map decide my priorities and go for few things on my each visit, because you can’t explore whole zoo in one day.