(CNN) — A village in France is offering a reward to anyone who can decipher a mysterious inscription on a local rock.

Experts in Plougastel-Daoulas, a village in Brittany, northwest France, have been unable to decrypt the inscription on a rock outside the village, estimated to be centuries old, the Agence France-Presse (AFP) news agency reports.

And so the authorities are turning the mystery over to the public, appealing to historians, academics, linguists, students and hobbyists to crack the code in exchange for a €2,000 ($2,240) reward.

There are letters, symbols and dates etched into the rock. FRED TANNEAU/AFP/Getty Images

The inscription comprises letters and symbols, one depicting a sailing boat. The language has not been identified: Dominique Cap, mayor of Plougastel-Daoulas, told AFP: "There are people who tell us that it's Basque and others who say it's Old Breton."

According to AFP, the as-yet impenetrable inscription reads in parts: "ROC AR B... DRE AR GRIO SE EVELOH AR VIRIONES BAOAVEL... R I OBBIIE: BRISBVILAR... FROIK...AL."

Local academics have pored over the rock since its rediscovery three or four years ago. "But we still have not managed to decipher the text," Cap said.

Michel Paugam, a municipal councilor who oversees local heritage, told AFP: "There are a lot of words, they're letters from our alphabet, but we can't read them, we can't make them out."

Local councilor Michel Paugam told AFP that local authorities can't make sense of the inscription. FRED TANNEAU/AFP/Getty Images

Two dates are also etched into the rock: 1786 and 1787. Véronique Martin, a local official who is leading the appeal, told AFP that the dates "correspond more or less" to the construction of forts and artillery batteries, including the adjacent Corbeau fort, built to protect the nearby harbor city of Brest.

After the public submit their suggestions, a jury will decide on the most likely interpretation of the inscription and award the €2,000 prize. "This inscription is a mystery and it is for this that we are launching the appeal," Martin said.