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 filled the 81 matrix grit (all D/T combinations) with at least one Cache including the attribute "Availabel in winter".
You can attach a proof to your log (optional).
Logs that don't fulfil this condition or contain a fake screenshot will be deleted without any comment.
As the owner of this Challenge Cache I have to fulfil the cache condition myself.
https://project-gc.com/Challenges/GCB045Y/93701
(There currently aren't any rules or guidelines regarding which date you should use when you log a Found it on a challenge that you have pre-signed. Project-GC however recommends that you use the date from when you visited, and signed, the challenge.)