Marnaton Formentera

The MARNATON eDreams Formentera by Balearia is an open water swimming race held in the open Mediterranean sea of Formentera, in Spain's Balearic Islands. Organized by MARNATON, the competition leads swimmers across the strait of Es Pas, turning the bay into a glowing pool of turquoise light.

Ses Illetes and Es Pas: courses of the Marnaton

Staged at the beginning of May, the event offers courses of 8 km, 4 km, and 2 km in the open sea. Swimmers taking on the premier 8 km distance set off from the western shore of Ses Illetes and make a direct crossing over Es Pas, navigating between sandbanks and open swells. The 4 km race starts from the eastern coast of the peninsula, while a dedicated 2 km course offers a sheltered route designed specifically for open water beginners looking to build confidence in pristine conditions. Course routes here are shaped by the elements and maritime geography. In past editions, swimmers have completed an 11 km circuit around the islet of S'Espalmador or crossed the open bay to finish directly on the sands of Es Pujols.

Nearly a thousand swimmers travel to Formentera to take part in these turquoise waters. When strong easterly gales whip up rough water along the headland, the race organizers move the competition to the sheltered western cove of Cala Saona, guaranteeing smooth, flat water for every stroke.

Ses Illetes: Posidonia meadows of Ses Salines

The sandy ribbon of Ses Illetes extends along the northern tip of Es Trucadors, protected within the borders of the Ses Salines Natural Park. The beach draws its name from the scattered chain of rocky islets and shoals. Behind the tideline, gentle dunes roll down into an exceptionally gradual white sand shelf, easing swimmers gently from the beach into open water. Even fifty meters out from the shoreline, the sea reaches a depth of only 1.5 meters. Underneath, vast underwater meadows of Posidonia oceanica blanket the seabed. These ancient seagrass prairies keep the water extraordinarily transparent and give the bay its crystalline clarity.

S'Espalmador: the wild islet across Es Pas

S'Espalmador is a solitary island stretching under three kilometers long and covering 137 hectares of preserved wilderness. Its perimeter is bounded by rugged sea cliffs, interrupted only by two protected coves to the south and northwest. The northwestern bay is sheltered by the islet of Illa de Sa Torreta, offering a natural haven for boats, while the lonely lighthouse of En Pou marks Illa des Porcs. Between Formentera and S'Espalmador lies the narrow channel of Es Pas. At low tide, it is technically possible to wade across the shallows between the two shores, though powerful tidal currents make unassisted crossings hazardous for casual visitors. During the organized race, this passage is transformed into an exhilarating, fully marshaled strait where swimmers push through the channel with complete safety support. Inland, the island shelters an ancient mud lagoon where bathing is now strictly prohibited under hefty fines to preserve the fragile wetland ecosystem.

The 1529 naval battle off Formentera's coast

These narrow straits and sheltered inlets have witnessed dramatic seafaring encounters across the centuries. In 1529, Ottoman commander Aydin Reis took refuge in a cove along the Formentera coast, hiding his fleet while waiting for unfavorable winds to turn. The calm coastal inlets that today offer shelter to open water swimmers once served as tactical hideouts for historic fleets navigating the Mediterranean. When a Spanish squadron intercepted the Ottoman ships off the coast, the encounter ended in a decisive maritime engagement known as the Battle of Formentera. The Ottoman forces captured seven of the eight imperial galleys near the island's shores, and the Spanish commander Rodrigo de Portuondo was killed in the battle. Today, the peaceful, sunlit turquoise water over the reefs carries no trace of that naval clash.

Cala Saona: pine forests and sunset beach life

Away from the northern sand spit, Cala Saona is an intimate cove bordered by a dense maritime pine forest. From the sand, coastal paths wind westward along the rocky bluffs toward the dramatic viewpoint of Punta Rasa. With just a single hotel set quietly on the beachfront, the cove retains an unhurried, secluded atmosphere throughout the early season. This sheltered cove provides the perfect setting for pre-race preparation, hosting a swim clinic on the eve of the competition where athletes get a feel for the water. The race weekend extends beyond the sea with morning yoga sessions and open-air sunset gatherings as evening falls across the island. It makes for a complete Mediterranean escape centered around clean water, quiet beaches, and the rhythm of the open sea.