Lago Fagnano is one of the most spectacular and remote fishing destinations in the world, a vast glacial lake stretching nearly 100 kilometers east to west across the heart of Tierra del Fuego, straddling the border between Argentina and Chile. Covering approximately 645 square kilometers, this enormous body of water plunges to a maximum depth of 449 meters, making it one of the deepest lakes in South America. Formed by glacial action and sitting atop the Fagnano-Magallanes fault — the boundary between the South American and Scotia tectonic plates — the lake is geologically active, slowly shifting eastward at roughly five millimeters per year. The Argentine portion accounts for about 606 square kilometers of the lake's surface, while the remaining 39 square kilometers lie within Chile's Magallanes y la Antártica Chilena Region. The southern bank is notably steep, while the northern shore expands into a wide, flat piedmont from which the surrounding plateaus are clearly visible. The lake's stony beaches, dramatic Andean backdrop, and surrounding lenga beech and Antarctic beech forests create an unforgettable setting for anglers. The town of Tolhuin sits near the eastern head of the lake and serves as the primary base for visiting fishermen. From the western end, the Azopardo River drains the lake toward the Almirantazgo Fjord in Chile.