I've been using this method for 4 years since buying a GPS. . You guys may already do this but I thought I would post it for some that don't. Do you have a GPS in your vehicle? If so just set it on "parks" while your driving around. We take trips for my Son's activities and short road trip get aways. What your looking for is parks that are named "City Park". City Parks are usually the oldest parks in any town. Also look for parks that are on streets like "Oak" or "Walnut". Any park that is on streets that are under 10th street. Parks at places like 3rd and Walnut are sure to be old. If I don't have time to stop I make note and research these parks online to see if they have potential. Give it a try and post your findings.....