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Puzzle CreationBeginner7 min read

How to Create a Puzzle Using Pigpen Cipher

Pigpen cipher transforms letters into angular symbols based on grid positions. It's visually striking and instantly recognisable, making it perfect for themed geocaching puzzles.

Understanding Pigpen

Pigpen (also called the Masonic cipher or Freemason's cipher) uses two grids:

  • Tic-tac-toe grid — Contains A-I (and J-R with dots)
  • X grid — Contains S-V (and W-Z with dots)

Standard grid layout:

A|B|C    J|K|L       S         W
-+-+-    -+-+-      / \       / \
D|E|F    M|N|O     T   U     X   Y
-+-+-    -+-+-      \ /       \ /
G|H|I    P|Q|R       V         Z
         (dots)             (dots)

Each letter is represented by the lines surrounding its position, with dots added for the second set in each grid.

Why Use Pigpen?

  • Visual impact — Symbols look mysterious and ancient
  • Instantly recognisable — Most puzzle solvers know it
  • Thematic flexibility — Perfect for Masonic, historical, or secret society themes
  • Easy to create — Can be drawn by hand or generated digitally
  • Physical integration — Symbols can be carved, painted, or formed from objects

Step 1: Encode Your Message

Use our Pigpen Cipher tool to generate symbols. Here's an example:

Message: CACHE

C = ⌐ (top-right corner of first grid)
A = ⌐ without right side (left corner)
C = ⌐
H = □ without top (bottom of grid)
E = □ (centre, all four sides)

Open Pigpen Cipher Tool

Step 2: Choose Your Presentation

Pigpen symbols can be presented in many creative ways:

Digital Images

Create a clean graphic with symbols in a row. Include in cache listing.

In-Field Elements

Symbols formed by fence sections, window frames, paving patterns, or architectural features.

Handwritten/Aged Look

Draw symbols to look like ancient manuscripts. Add coffee stains or burned edges for effect.

3D Objects

Arrange sticks, stones, or other objects to form symbol shapes.

Part of Art

Hide symbols within a larger illustration or photograph.

Pigpen Variations

Several variants exist that can add difficulty or theme:

Standard Pigpen

The classic version with tic-tac-toe and X grids.

Templar Cipher

Uses crosses instead of X grids. See our Templar Cipher tool.

Rosicrucian Cipher

Alternative grid arrangements with different dot placements.

Custom Key

Rearrange letters in the grids for a unique cipher key.

Difficulty Variations

Easy (D1-D1.5)

  • • Use standard Pigpen with clear symbols
  • • Include a key or reference chart
  • • Mention "Pigpen" or "Masonic cipher" in description
  • • Clear spacing between letters/words

Medium (D2-D2.5)

  • • Don't name the cipher—use thematic hints
  • • Symbols integrated into images or artwork
  • • No word separators
  • • Use a lesser-known variant

Hard (D3+)

  • • Custom grid arrangement (non-standard key)
  • • Symbols rotated or flipped
  • • Combined with another cipher layer
  • • Symbols formed by field elements requiring site visit

Complete Example Puzzle

Cache Title: "The Mason's Mark"

Theme: Historic Masonic lodge in the area

Cache description excerpt:

"The Freemasons of old knew the value of secret communication. Their symbols adorned buildings and documents alike. This ancient mark was found carved into the foundation stone of the old lodge. What secrets does it hold?"

[Image showing Pigpen symbols spelling "NORTH GATE"]

Solution process:

1. Recognise Pigpen from angular symbols and Masonic theme
2. Decode each symbol using standard Pigpen grid
3. Message: NORTH GATE
4. Head to the north gate of the local historic building

Pro Tips

  • Draw clearly. Make sure symbols are unambiguous— dots should be clearly visible, corners should be sharp.
  • Test with fresh eyes. Have someone unfamiliar with your puzzle decode it to ensure symbols are readable.
  • Consider similar letters. Some symbols look similar (like J and A, or K and B). Avoid words where confusion could arise.
  • Match the theme. Pigpen works best with historical, mysterious, or secret society themes. It feels out of place in modern contexts.