Baía de Marajó is a large bay at the mouth of the Amazon River in Pará, Brazil, forming a significant part of the estuary system around Marajó Island. The bay presents a challenging paddling environment due to its exposure to open water conditions. During the summer months, ceaseless trade winds whip up substantial foaming waves across this expansive water body, indicating significant wind exposure and fetch. Paddlers should anticipate strong, consistent winds capable of creating rough water, particularly in the summer season. The bay is bordered by several beaches that can serve as potential access points, including Praia do Pesqueiro and the more secluded Praia Da Maloca near Soure. Praia Da Maloca is noted for its expansive sandy shores and proximity to lush mangrove ecosystems, which could offer sheltered paddling routes and wildlife viewing opportunities. The surrounding landscapes feature rich cultural heritage rooted in local traditions. The bay's waters are deep in its central areas, with recorded depths between 8 to 25 meters near points like Ponta do Carmo and Colares. Given the bay's connection to the Amazon River's outflow and the Atlantic Ocean, paddlers must be prepared for powerful tidal currents, strong winds, and potentially large waves, requiring advanced skills and careful trip planning focused on wind forecasts and tide stages. The area is used for scientific research, indicating a level of accessibility, but no specific paddling regulations or facilities are detailed.