Río Santa Cruz is one of Patagonia's most dramatic and visually arresting fisheries — a massive, glacially-fed river that cuts a bold, milky-blue path across the arid Patagonian plateau for 382 kilometers before emptying into the Atlantic Ocean. Fed primarily by two enormous glacial lakes, Lago Viedma and Lago Argentino, the river carries an almost surreal volume of cold, turbid glacial meltwater that gives it a striking, otherworldly appearance — particularly vivid on sunny days when the water takes on an intense turquoise-blue hue. This is big water in every sense: wide, powerful, and demanding. It is not a river for the faint of heart or the casual angler, but for those drawn to migratory fish, raw Patagonian wilderness, and the kind of fishing that rewards patience and persistence, it offers an experience unlike almost anywhere else on Earth. The river's most celebrated distinction is that it hosts the only known run of anadromous rainbow trout — steelhead — along the entire Atlantic coastline of South America, making it a genuinely singular destination in the global fly fishing world.