The best time to go is in the fall and spring. Summer and winter, not so much. It really is a beautiful place to drive around or hike. They just opened a new children's area that is fabulous. All that being said, I don't understand the cost involved to go see trees. Again, I am a cheapskate so perhaps that is my problem, but it seems like a lot of money to just go look at trees, trees that have been planted in an area I can hear the traffic from rt 53 and I 88.
So yes, it's definitely worth going to at least once (definitely the fall) but you could easily go to a forest preserve and have an equally lovely time for free.
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