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AR_ The Gray Matter Sodality Mystery Cache

This cache is temporarily unavailable.

PatientRock: I’ll swing by as soon as I can to check it out.

Hidden : 06/12/2018
3.5 out of 5
2.5 out of 5

Size: Size:   regular (regular)

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How Geocaching Works

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Geocache Description:

The geocache is not at the posted coordinates, however, the posted coordinates are where you start this adventure. This is a special “augmented reality” geocache where you must use a smartphone app called Zappar to follow clues to the actual geocache location. Zappar is available for iOS (Apple) and for Android devices. Zappar is free and does not require that you sign up for an account to use it.

iOS (Apple Devices)

To get started, find the sign in the below picture (also in the gallery). On that sign somewhere is a strange symbol. Scan that symbol with Zappar and you'll be guided to another strange symbol. Be sure to fully scan the images to let the content load completely.

Bear in mind that the trails here can get a little muddy so wear appropriate shoes. Also, like much of Maryland's woods, come ready for ticks, mosquitoes, and poison ivy. The final will require off-trail travel.


Greetings Initiate,

The Gray Matter Sodality finds itself in a tricky situation. We had made arrangements to purchase a fragment of Albert Einstein’s brain from a black market dealer and were nearing final terms when the seller decided to open the sale to other offers. We cannot let this fragment slip from our grasp as it then may never been seen again. We are temporarily promoting you to [rank:] Reclaimer to go retrieve that fragment. We have received information that the black market dealer has stored it in the woods here somewhere. Do not fail us.

Artemis Shoal
Executive Director
The Gray Matter Sodality



“This cache is part of an experiment that allows the use of Augmented Reality (AR) apps to find the cache. At the end of this experiment, Geocaching HQ will decide if this cache will be grandfathered or archived. Geocaching HQ reserves the right to archive this cache at any time if conditions change. If you have found this cache and would like to give feedback on your experience, please fill out this survey.”

Additional Hints (Decrypt)

Srry serr gb zrffntr zr vs lbh unir nal vffhrf nybat gur jnl. Gur svany vf erthyne-fvmrq ghccrejner cynprq bhg va gur bcra.

Decryption Key


(letter above equals below, and vice versa)