Michel Augustin Francis Siffre (.mw-parser-output .IPA-label-small{font-size:85%}.mw-parser-output .references .IPA-label-small,.mw-parser-output .infobox .IPA-label-small,.mw-parser-output .navbox .IPA-label-small{font-size:100%}French: [sifʁ]; 3 January 1939 – 25 August 2024) was a French geologist, speleologist and underground explorer. He is especially known for the chronobiology experiments he conducted on himself.
Siffre was born and raised in Nice, France. His parents were Jean and Luci...