This cache is a challenge cache:
It is at the posted coordinates, even though it is an "unknown" cache type.
You are not allowed to log a "find" without proof that you qualify by completing the caching related "challenge" below, but you can make a write note.
Challenge:
To log this cache, you must have found and logged one cacheor more on every different (366) calendar days.
You can attach a proof to your log (optional).
Logs that don't fulfil this condition will be deleted without any comment.
As the owner of a challengecache I have to fulfil the cache condition myself.
https://project-gc.com/Challenges/GCA3REN/74281