You can get it online at the will county website
Go to Will County Forest preserve office at 501 romeo rd romeoville
Thank you all for your answers, I normally just walk my dog on the grass near the lakes away from the bikers.
I originally made the mistake of bringing my dogs with me, thinking we could go to the dog park right after. Dogs aren't allowed in the Park District building but there is a post outside the front door that you can tie their leash to. The next time, I left the dogs at home. They'll ask you your dog's breed, they'll make you a pass with a lanyard. You'll get a pass for each dog you own.
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