Circuito MASF — Colégio Naval (Angra dos Reis)

On December 15, 1591, the English privateer Thomas Cavendish launched a violent raid on Ilha Grande, looting local settlements and torching homes before turning his fleet toward Ilhabela. Centuries later, the calm waters of Angra dos Reis serve as the stage for a very different kind of encounter, where participants in the Circuito MASF gather to test their performance in a setting defined by both military history and maritime resilience. The race is hosted at the Colégio Naval, a site that bridges the gap between the region's colonial past and its modern identity as a hub for aquatic sports in Brazil.

A landscape of history and currents

As you navigate the course, you are swimming through a geography marked by human intervention and scientific intrigue. Not far from these waters, the 1869 Angra dos Reis meteorite fall remains a point of fascination, as this bay is the only place in the world to have witnessed the descent of an 'angrite' class meteorite, with rumors of a final, hidden fragment still resting on the seabed. While you focus on your stroke, you are also traversing the waters that once connected to the Lazareto, a 19th-century quarantine station that processed over 4,000 ships. The structures that supported these operations, including the historic aqueduct, stand as silent witnesses to the endurance of those who arrived here during the cholera outbreaks of the empire. This sense of historical gravity is balanced by the immediate challenge of the MASF circuit, which has been pushing athletes to evolve since 2014 through a focus on professional safety and technical consistency.

Race day and logistics

The Circuito MASF at Colégio Naval offers distances of 500m, 1250m, and 1500m, designed for those seeking a clear, measured progression in their open water journey. Given the logistical complexity of organizing events in an active naval environment, the registration fees vary by period, starting at R$ 180 in the initial lot and reaching R$ 486 for late entries. This professional approach ensures that the race remains a reliable fixture for swimmers who appreciate strict operational oversight. If you are looking to continue your season in the same region, you will find Invasão da Ilha Grande taking place just one day later, offering a distinct challenge for those ready to commit to a full weekend of endurance swimming in the bay.