Cap Naïo

The Open Swim Stars event in Cassis provides six race distances ranging from 500m to 10km, held annually in the Mediterranean sea on June 7, 2026. This coastal stretch requires familiarity with open-water navigation, as the course follows the rugged limestone cliffs of the Calanques. The area serves as a marine nursery, where specific zones are strictly protected to allow fish stock replenishment; swimmers must remain within the marked buoys, as fishing and other human activities are prohibited in these nurseries to ensure biodiversity recovery.

Historical context of the route

Swimming these waters means traversing a site central to maritime trade since the Roman era, when the port was known as 'Carsicis Portus' and served as a vital node for Antoninus Pius's shipping routes. Beneath the surface, the geological profile is equally ancient, with the Grotte des Trémies containing human remains dating to the Lower Paleolithic, visible to those familiar with the underwater topography of the massif. The coastline itself was shaped by the extraction of the 'Pierre de Cassis', a durable limestone exported across the Mediterranean to build quays in cities from Algiers to Alexandria.

Competitors should be aware of the military history attached to the harbor. On April 17, 1813, the British Royal Navy conducted a raid here, successfully destroying the batteries positioned at the Château de Cassis to disrupt local defenses. This tactical history contrasts with the current recreational use of the bay, which sits just a few months before the Défi de Monte-Cristo in La Ciotat, allowing swimmers to transition from this steep cliff-side course to the longer endurance challenges scheduled for September. The event maintains a focus on safety and standardized technical support, providing clear sightlines along the headlands that define this historic Provençal port.