Lago Paimún is a stunning glacial lake nestled in the Andean mountains of Neuquén Province, Patagonia, Argentina, within the boundaries of Lanín National Park. Stretching approximately 11 kilometers in length, it forms the northern arm of the greater Huechulafquen lake system — a trio of connected lakes that together create one of the most impressive and diverse fishing water systems in all of Patagonia. The lake sits beneath the imposing Lanín volcano, which rises to 3,740 meters and dominates the northern shoreline, its glaciers feeding the lake along with small streams originating at the Chilean border. The surrounding landscape is characterized by distinctive volcanic beaches with black sand, a direct result of the volcanic geology of the region. The lake lies within an indigenous Mapuche reservation, and a road runs along the northern shore passing through several Mapuche communities, offering anglers a glimpse into a culturally rich and largely unspoiled corner of Patagonia.