The Castle Code

The bus bumped up the hill, and there it was: Stonecrest Castle, with four round towers and a flag snapping in the wind. Lily pressed her nose to the window. "It's real!"

Their guide, Mr. Whitlock, led the class through the great hall, where long tables stood beneath banners and a huge fireplace could fit three grown-ups standing up.

"Castles were built as homes and as fortresses," he explained. "The thick walls and tall towers protected the people inside."

In the library tower, Lily and her friend Sam lingered by an old wooden desk. Carved into its side were strange letters: IULHQGV IRUHYHU.

"Is that another language?" Sam whispered.

Mr. Whitlock smiled. "No. That's a code. Long ago, people who wanted to send secret messages used a trick called a shift cipher. Each letter is replaced by the letter three places later in the alphabet. A becomes D. B becomes E. C becomes F."

"So to decode it," Lily said slowly, "we go three letters back!"

Sam grabbed his notebook and wrote the alphabet across the top. They worked on the first word together. I goes back to F. U goes back to R. L goes back to I. H goes back to E...

"F-R-I-E..." Sam started.

Can you finish it? Try it yourself before you read on!

Lily finished the first word: "FRIENDS." Then the second: I-R-U-H-Y-H-U became F-O-R-E-V-E-R.

"Friends forever," Sam read. "Someone carved that here hundreds of years ago."

Mr. Whitlock nodded. "The castle records say two young pages — boys who worked here while training to become knights — were best friends. Historians think they left this message."

On the bus ride home, Lily and Sam invented their own secret code using the same three-letter shift. For the rest of the year, they passed notes that no one else could read.

The very first one Lily wrote said: FRGH EUHDNHUV.

Sam decoded it in ten seconds and grinned: "Code breakers."

⭐ The End ⭐