Seno de Reloncaví is a semi-enclosed sound, a nearly circular saltwater system with an average diameter of 30 kilometers, located in the Los Lagos Region of Chilean Patagonia. It receives inputs from the Reloncaví Fjord and serves as a gateway to the Chiloé Archipelago and Western Patagonia. The northern end of the sound is dominated by the port city of Puerto Montt, a major hub for Chile's salmon industry. The sound features a significant intertidal area and sheltered waters, with a coastline rich in archaeological sites like ancient fishing corrals and shell middens, indicating a long history of marine subsistence. The surrounding landscape is dramatic, with deep fjord dynamics influencing the water body.