This is a letterbox, please don't take the stamp
At the posted coordinates you will find a trail marker.
If the number on the marker is 22 then final is at N39 02.557 W84 07.584
If 6 then the the final is at N39 02.589 W84 07.567
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Alternate solution: from the posted coordinates go 65 feet at a bearing of 21o (degrees) true
ODNR Permit EF-06-11-24
See https://coord.info/GCARY9Y for parking and trailhead info
Here's a great park map https://drive.google.com/file/d/1vN-M0wnOxctzyuZbwmqZ-M6wVak81Z9Z/view?usp=sharing
You are looking for a metal water bottle behind a 3 foot diameter log under a small rock pile.