Étretat

Étretat is the setting invoked by a deciphered message that points toward the Aiguille Creuse, the hollow coastal formation associated with Arsène Lupin. In the discussion of Ingolf’s codes, the place’s real landscape and literary legend offer a plausible destination—and a ready-made story for anyone determined to connect the Templars to the message.

The Message and Its Destination

The second wheel, applied to the third letters of the coded words, produces the phrase “chambre des demoiselles, 1’aiguille creuse.” A fuller decipherment gives directions to a chamber downstream of Étretat, beneath Fort de Fréfossé, and to the Aiguille Creuse. The sequence makes Étretat seem not merely an allusion but the site at which the message’s clues converge.

The Aiguille Creuse and Lupin

The Aiguille Creuse is described as a natural castle at the edge of the beach, hollow and habitable within. The explanation associates it with the secret of Arsène Lupin and recounts a legend in which the formation served as Julius Caesar’s secret weapon during his invasion of Gaul, and later as a refuge for the kings of France. These claims belong to the story attached to the landmark; they are part of the mystery’s literary and legendary texture, not independent confirmation of the code’s historical origin.

The Lupin connection helps explain why Ingolf might have chosen the place. Lupin enthusiasts make pilgrimages to Étretat, search for secret passages, and construct anagrams from Maurice Leblanc’s writing. Ingolf is characterized as an enthusiast of Lupin as well as Rosicrucian lore, making the coded allusion consistent with his interests and his taste for elaborate puzzles.

A Clue That Invites Overinterpretation

The destination does not establish a Templar secret. The investigators can imagine arguing that the Templars knew the Aiguille Creuse’s secret and that the message was therefore written at Provins in the fourteenth century. But that is precisely an added interpretive story, not something the Étretat reference proves. The code’s apparent historical depth can be explained more simply by Ingolf’s modern play with literary material: a third message, decoded through another wheel, curses the labor of writing in cryptic form in modern French. Étretat thus functions as both a concrete coastal destination in the decipherment and a test of how readily an evocative place-name can be recruited into an unfounded historical pattern.