Route Cipher
Encode and decode using the Route cipher. A transposition cipher that writes text in a grid and reads it in a pattern.
Route Patterns
Spiral CW: Start top-left, go right, spiral inward clockwise
Spiral CCW: Start top-left, go down, spiral inward counter-clockwise
Snake H: Left-right, right-left, alternating rows
Snake V: Top-down, bottom-up, alternating columns
Columns: Read each column top-to-bottom
Rows: Standard left-to-right, top-to-bottom
Puzzle Tips
- • Try different column counts - text length hints at dimensions
- • Look for factors of the text length
- • Civil War messages often used route ciphers
- • The route pattern itself might be a clue
What is the Route Cipher?
The Route cipher is a transposition cipher where the plaintext is written into a grid and then read off following a specific path or route. The letters aren't changed, just rearranged.
How It Works
Encryption
- Write the plaintext into a grid row by row
- Choose a route pattern (spiral, snake, columns, etc.)
- Read off the letters following that route
Decryption
- Write the ciphertext following the route pattern
- Read off row by row to get plaintext
Common Routes
- Spiral: Start at corner, spiral inward
- Snake/Boustrophedon: Alternating direction each row/column
- Diagonal: Read along diagonals
- Columns: Read down each column
Route Cipher in Geocaching
This cipher appears in puzzles because:
- Visual: Grid and path make interesting puzzle images
- Multiple solutions: Different routes give different ciphertexts
- Historical: Used in Civil War
- Flexible: Custom routes can be created
Historical Use
The route cipher was famously used during the American Civil War. Union forces used it extensively, with the route pattern serving as a second layer of security along with the grid dimensions.
Cryptanalysis
- Grid size: Try factors of the message length
- Pattern recognition: Common words might partially appear
- Multiple anagramming: Try rearranging letter groups
- Frequency: Letter frequencies match plaintext