Maratona Aquática de Porto Belo

Porto Belo sets the stage for the Maratona Aquática de Porto Belo, an open water swimming race in the sea of Porto Belo, in southern Brazil. Organized by Correr E Nadar, the gathering takes place in January during the warmth of the southern hemisphere summer. It offers an ideal introduction to sea swimming in conditions that feel far more like an emerald lake than an exposed ocean passage. The competition takes place entirely inside the sheltered bay, where João da Cunha Island stands as a massive breakwater, shielding the race area from incoming swells and ensuring flat, mirror-like water. Swimmers can choose from distances tailored to every experience level, with courses set at 200, 600, 1,500, and 3,000 meters.

The bay is a popular coastal destination, which means motorboats and jet skis share the surrounding bay, but swimmers need not worry about stray watercraft entering their path. Organizers set out clear guide buoys that define an exclusive swimmer corridor along the beach, keeping every athlete safely apart from motorized boat lanes so you can focus entirely on your stroke and pacing.

Baía de Porto Belo: a clear water nursery behind the island

The bay inside the island is renowned for its clear waters, which function as a thriving natural nursery for diverse marine life. The island barrier keeps the water calm and sediments settled, allowing swimmers to look down into an unusually clean aquatic world while paddling across the bay. In this protected pocket of the coastline, the seabed provides shelter where aquatic species flourish sheltered from the heavier ocean surf. That biological vitality extends along the rocky margins that fringe the racing basin. At Costão das Vieiras, a rocky headland that divides Porto Belo bay from neighboring Perequê, scallops once carpeted the stones, giving the headland its name after the edible shellfish that thrived in the shallows.

Praia do Centro: Carijó grinding stones and ancient rock art

Right on the sands of the central town beach where the event gathers, human history is inscribed directly into the seaside rocks. At the water's edge lie the 'panelas de bugre', smooth depressions and basins worn into coastal boulders where Carijó people of the Tupi-Guarani tradition sat to sharpen and polish their stone tools and weapons. Standing on the shoreline before diving in, you can see these prehistoric workshops resting right where the tide washes over the stone. These seaside grinding stones are only a fraction of the deep human past preserved around the bay. The municipality is home to twelve officially registered archaeological sites, ranging from rock inscriptions to ancient coastal shell mounds known as sambaquis. Across the narrow passage on Ilha de Porto Belo, a 1.3-kilometer ecological trail winds through the forest past petroglyphs and rock engravings created 4,000 years ago, leaving an indelible imprint of the area's earliest maritime inhabitants.

Ilha João da Cunha: whale oil mortar and traditional mullet runs

Centuries after the indigenous Carijó shaped their stone weapons on the shoreline, the offshore island became the center of a very different maritime enterprise. Around 1824, João da Cunha Bittencourt constructed a whale oil processing station on the island. The 'Arrasto de Praia da Tainha' has been officially recognized as cultural heritage, preserving a seasonal rhythm that still brings coastal residents together on the sand.

Caixa d'Aço and the secluded coves of the peninsula

Beyond the central race beach, the shoreline unfolds into a series of celebrated coastal havens. Caixa d'Aço is an internationally acclaimed natural harbor. At Praia do Araçá, a traditional fishing community maintains Azorean maritime customs. The coastline opens up into Praia do Perequê, the municipality's longest beach stretching for 2.5 kilometers. Its calm waters and tree-lined shore welcome beachgoers, though at high tide its strip of fine white sand is almost entirely swallowed by the sea. For those willing to venture further off the beaten track, Praia do Estaleiro offers a completely secluded coastal refuge. Measuring just 80 meters in length, this pocket beach cannot be reached by car, requiring visitors to hike in along a footpath or approach quietly from the sea.