Check on the Springfield IL. Web site under things to do and it will tell you about all the events.
I live close to the park. It was held several weeks ago. Sorry.
Not sure they hold that event anymore. It used to be held up the hill in that little area between New Salem and Mentor Grahams gravesite.
I don't know! I didn't even know they had a blue grass festival! Sorry I cannot help you
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