This is a Challenge Cache and IS located at the posted coordinates. In order to claim a find you must have met the terms of the challenge. You may sign the log at any time and post a note on the cache page. Any "found it" logs that don't qualify will be deleted. There is a challenge checker you can run to see if you qualify.
Congrats to NoBigDipper on the FTF!
What a challenge. I found this in Missouri and it took me 17 months to complete. I loved it and grew as a geocacher. There are cachers in the area who will qualify immediately but for the rest of you, it is something to work towards.
The challenge is to find a mystery cache on 200 different days of the year. The year does not matter. You can use the checker below and have fun.
Location: Google maps will have you stop on the highway to get this. Do not do that. Go to the Mill Creek Trailhead. There is plenty of safe parking.
Cathy'sClown has used "Project-GC Challenge Checker") to see if they qualified for this challenge and they did. 201 dates of 200 completed.