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SURVIVOR18: Mayfield Earthwork Fort

A cache by Awesnap Send Message to Owner Message this owner
Hidden : 11/02/2018
3 out of 5
2 out of 5

Size: Size: regular (regular)

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How Geocaching Works

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Geocache Description:

The posted coordinates are for the parking lot where you will start this geocache adventure. Mayfield Earthwork Fort is a city of Manassas park, therefore it is open from sunrise to sunset daily. Absolutely no night caching. Off the trail there are a lot of groundhog holes so watch your step.

Mayfield Fort Historic Site preserves one of the few remaining portions of the Civil War fortifications built to protect the vital rail junction at Manassas, Virginia. Covering 11 acres, the Mayfield Fort site is located on high ground between Buckhall and Russia Branches. Both are tributaries to the Occoquan River and strategic point between them was an ideal place for a Confederate fortification.

For this puzzle cache you will need to visit five signs to locate 4 numbers and four letters. These will be used to locate and unlock the geocache. You will also have to decode the "lock combo" using a CSA Cipher Disk that is on the final container or posted on this cache page.

To Find the Geocache Container

This geocache requires you to visit four locations to gather information. You will visit signs and find numbers for ABCD to be plugged into the partial coordinates below.

Geocache is at: N 38° 45.2AB W 77° 27.1CD

Waypoint Sign 1: A Civil War Redoubt SIGN IS MISSING: Answer B=3
  • B = A 300-yard trail from the parking lot to the fort rises at what percent grade?
Waypoint Sign 2: Fortifying the Junction
  • A = Number of letters in the name of the camp written on the top right corner of the "Proclamation" on June 5th, 1861.
Waypoint Sign 3: Monster Manassas - How Strong a Stronghold?
  • D = How many months that "Monster Manassas has been the fright and bugbear of the country."
Waypoint Sign 4: The People and the Land
  • C = Last digit of the year that that Robert Howson Hooe purchased the 160 acres of Mayfield.
The checksum of ABCD is 27


To Unlock the Geocache

This geocache requires a you to find a four letter codeword that you will have encrypt and typed into the Certitude checker below to get the 4 digit combo unlock the geocache. Using the three word title (17 letters total) at the posted sign you will count from left to right to form a strange word.

Waypoint Sign 5: *****************
  • 1 = 4th letter in the title.
  • 2 = 8th letter in the title.
  • 3 = 17th letter in the title.
  • 4 = 1st letter in the title.

The Confederate Army Cipher Disk

During the Civil War, if signals were to be displayed in the presence of an enemy, they were guarded by ciphers. These ciphers were capable of frequent changes. The Confederate Cipher Disk was a mechanical wheel cipher consisting of two concentric disks, each with the 26 letters of the Latin alphabet, that was used for the encryption of messages. It was created by Francis LaBarre and was based on the Vigenère Cipher.

For this geocache we are using it as a simple substitution cipher as it set on the container at the GZ (or use the same cipher disk as it is set in the picture below). Use the top row of the cipher disk to match up with the coded lock combo below. For instance, if your four letter word from the sign was "CROW" the cyphered jumble from the disk would be "LAXF." Enter this into the Certitude Checker below to open the box.


Please be gentle with the container and remember to put everything back and lock the container when you are done. If you get stuck, have problems with coding, or want to report damage message me from or email at

This is one of fifteen geocaches placed in conjunction with the Northern Virginia Geocaching Organization’s 2018 Annual Series: SURVIVOR18. To learn more about NoVAGO’s Survivor game go or to play along click on this LINK.


and CACHE of the YEAR.

Approved by Christen Fox, CPRP

Additional Hints (No hints available.)

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