The cache is NOT at the posted coordinates.
You will need the Groundspeak (geocaching.com) Adventure Lab mobile app on your smartphone or tablet.
In order to get the final coordinates, you must complete the Adventure Lab, Come Play at Forrester Acres! It will require a data and/or a wi-fi connection.
Use the clues at the completion of each stage to find the final coordinates.
Click here to get started.
I suggest approaching the cache from the park side.
Congratulations to sheppard4, who had the park to theirself for the FTF!
This cache is part of the series, MountainHobbit's Mathoms, Year 17. Don't know what a mathom is? Check out Chapter 1 in the Fellowship of the Ring by J. R. R. Tolkien to find out the reason for this hobbity celebration!