Bahía de San Antonio is a coastal bay located in Río Negro, Argentina, forming part of the larger Golfo San Matías. It is designated as a Natural Protected Area, emphasizing conservation and eco-tourism, which helps preserve its pristine sandy shores and diverse marine ecosystem. The bay is known for its calm ambiance, gentle waves, and remarkably clear, turquoise waters, a characteristic of the "Patagonian Caribbean" coastline that includes nearby beaches like Las Grutas, Punta Perdices, and Las Conchillas. A significant microclimate influenced by the gulf can result in warmer coastal water temperatures, reaching up to 25°C during the summer season, which is atypically warm for Patagonia. The bay's landscape is dynamic, with the tidal cycle dramatically changing the scenery; at Punta Perdices, for example, turquoise ponds fill as the tide rises. Paddling activities such as kayaking and stand-up paddling are popular water sports here. The area offers a blend of tranquility and outdoor activity, with panoramic views and a relaxed vibe. Key access points for paddlers include the vicinity of Las Grutas and the Puerto de San Antonio Este, which borders the bay. Wildlife of note includes a resident population of bottlenose dolphins, which are the subject of ongoing scientific study, and the area is also known for bird watching. Paddlers should be aware of the significant tidal range, which necessitates careful planning for launch and landing times, and should expect potential wind exposure common to the Patagonian coast.