A potentially lucrative treasure hunt is being offered to the public, though to crack the entire thing you'll need to know French—or at least partner with somebody who does. The latter idea is actually one of the points of the unusual challenge. Artist Michel Becker is the mastermind, and the Guardian lays out the broad strokes: He's put out a book in the UK and another in France. Each contains a series of codes and riddles to be solved, and the answers will reveal the location of a buried key, half of which is in each country. Find both halves, and you win the grand prize: a decorative golden box that the UK gave to France in 1904 to commemorate a peace pact known as the Entente Cordiale. It's valued at about $900,000. The books cost about $30 apiece at the Golden Treasure of the Entente Cordiale website. You can view a "trailer" for the hunt here.
"A paper and a pencil will be enough to discover some solutions," write Becker and Vincenzo Bianca, who teamed with Becker to create the puzzles. "For others, you will need to do additional research," though they say the internet should suffice. "This is not an easy treasure hunt," they add. Becker's own track record might prove that point. The Telegraph notes that he teamed with a different partner back in 1993 to create another treasure hunt—the riddle of the Golden Owl—and it remains unsolved. According to Bianca, Becker obtained the golden "casket" being offered in the latest puzzle at auction and "fell in love" with the story behind it and its symbolization of peace. "He doesn’t hope to make any money from this operation, but at least he hopes to break even," adds Bianca. "If people are passionate about the adventure, he will have achieved what he wanted." (Read more treasure hunt stories.)