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SGTF: Sadly, power company construction is encroaching on this cache.


FBZ A.P.E. 51: Stone of the Lost Valley

A cache by Simian Guerrilla Task Force (SGTF) Send Message to Owner Message this owner
Hidden : 7/13/2008
2.5 out of 5
3.5 out of 5

Size: Size: regular (regular)

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Geocache Description:

Please note there are additional waypoints published with this cache!

At this FBZ, you have been provided the 1st of a series of codewords needed to unlock details surrounding the final mission of Operation Silverback. Use SGTF’s cipher to decode secret writings discovered during this and other FBZ adventures.

In all, there are a total of seven (7) caches encompassing this series. Six FBZs contain “intelligence” report(s) and a corresponding secret codeword. Enter these six (6) codewords collectively in the codewords panel at Forbidden Zone Geocaches to unlock coordinates to the seventh and final TOP SECRET FBZ location. Keep in mind that codewords can be gathered in any order so you DO NOT need to visit FBZs sequentially!

Mission Details:
At this TSG you have been provided with a piece of “ancient” shale rock which will direct you to a nearby shaman burial spot where you can discover the first mission codeword for Operation Silverback (UPDATE 1/16/16: codeword has been relocated to the ammo can). Use the "pig-pen" or masonic cipher to help decode the symbols on the rock and all subsequent secret writings you find during your participation in SGTF’s black project (a.k.a. “The Activity”).

FBZs are reserved for POTAM related to SGTF's Silverback operations. Visitors are encouraged to register their visit and leave ONLY items containing relevance to The Planet of the Apes or items that are traditional hitchhikers (e.g. geocoins, travel bugs, etc.). Only place and/or remove TRACKABLE items from this cache (read NO unrelated SWAG); Any POTAM found in this cache designated as NOT TRACKABLE is pertinent to operations for this FBZ and should REMAIN ASSIGNED TO THE CACHE. POTAM labeled PROVISIONAL FTF is considered remittance as reward for the FTF (First to Find) and can be removed freely without restriction or stipulation.

Don't miss the fantastic overlooks in this area including an inspiring view of San Diego & Arizona Eastern Railway ("The Impossible Railway") trestle from the Sacatone Overlook. Click here to read more about this exhilarating track of land!

Additional Hints (Decrypt)

pyvzo ebpxf oruvaq ynetr obhyqref gb ryringrq nern gura ybbx va perivpr gbjneqf sebag bs fyno

Decryption Key


(letter above equals below, and vice versa)



  • Carrizo Gorge RailwayDon't miss the fantastic overlooks in this area including an inspiring view of San Diego & Arizona Eastern Railway ("The Impossible Railway") trestle in Carrizo Gorge. Photo taken from Sacatone Overlook. To get there, take the Sacatone Spring Road spur (high clearance vechicles only) off McCain Valley Road 2.8 miles north of Old Highway 80.
  • Rain Clouds Over The Lost Valley
  • Stone of the Lost ValleyAn intimidating view of the "sacred" Stone of the Lost Valley which has been rumored to protect SGTF's Forbidden Zone A-51 cache.

68 Logged Visits

Found it 53     Didn't find it 2     Write note 10     Temporarily Disable Listing 1     Publish Listing 1     Owner Maintenance 1     

View Logbook | View the Image Gallery of 31 images

**Warning! Spoilers may be included in the descriptions or links.

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Coordinates are in the WGS84 datum

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