A scientific expedition led by diver and naturalist Laurent Ballesta is investigating the origin of hundreds of regular circles found on the Mediterranean seabed [1, 2].

The discovery challenges existing understanding of deep-sea geological or biological formations. Because the rings appear in such a regular pattern, they suggest a specific, repeatable process that requires multidisciplinary analysis to explain.

The mystery began in 2011 when sonar scans first detected the formations [3]. These circles are located approximately 20 kilometers [2] off the coast of Cap Corse, situated within the Cap Corse and Agriate marine natural park [2, 3]. The formations reside at a depth of 120 meters [2].

Researchers have identified between 1,400 [2] and 1,417 [3] of these rings. The sheer number and regularity of the circles prompted Ballesta to organize a multidisciplinary scientific expedition to determine if they were created by natural phenomena or other means [1, 2].

The findings of this investigation were detailed in a documentary that aired on May 3, 2025 [3]. The film explores the process of discovery and the scientific methods used to probe the seabed. The documentary remains available for viewing through August 3, 2027 [1].

Ballesta's work focuses on the intersection of exploration and marine science. By utilizing advanced sonar and diving techniques, the team aimed to pierce the mystery of how these specific shapes formed in a concentrated area of the Mediterranean [1, 2].

“1,417 regular circles on the seabed”

The identification of over 1,400 geometric formations suggests a systematic environmental or biological process occurring at 120 meters depth. While the sonar data provides the scale of the phenomenon, the multidisciplinary approach led by Ballesta is necessary to distinguish between rare geological anomalies and potential biological engineering, potentially revealing new insights into the Mediterranean's benthic ecosystems.