Rafting on the Hua Hum River

Rafting on the Hua Hum River stands as one of the most singular experiences in the San Martín de los Andes region, distinguished not only by the moderate adrenaline of its rapids but also by the extraordinary geographical and biological setting it traverses. Located about 30 kilometers from the city, in the heart of Lanín National Park, the Hua Hum River is one of the few watercourses that, after originating in the Lácar and Nonthué lake basin, flows westward to cross the Andes and eventually empty into the Pacific Ocean through a complex network of lakes and rivers in Chile.

The adventure typically begins in the Hua Hum area, a name that in the Mapuche language evokes a “hole in the sky” or a “place where it rains.” After receiving the necessary equipment—which includes dry jackets, life vests, and oars—rafters attend a safety briefing or navigation “clinic.” Here, the fundamental commands from the guide are learned to coordinate rowing and weight balance in the raft, crucial elements for navigating the river’s obstacles. Starting from the old wooden pier at Lake Nonthué, the boats launch into a journey of approximately eight to ten kilometers through glacial meltwaters that display a very particular milky turquoise or emerald hue.

As the raft moves forward, rafters witness a fascinating and rare ecological transition for other latitudes of Argentine Patagonia. The Patagonian Andean forest of coihues and lengas quickly transforms into the Valdivian jungle. This ecosystem, nurtured by the extremely high rainfall in this corner of the mountains, manifests in an explosion of plant density: giant ferns, mosses, lichens, and monumental nalca leaves cover every inch of the riverbanks. In this environment of deep greens, it is common to spot specialized birds such as the kingfisher, white herons, and the torrent duck, a species expert at diving in the strongest currents.

Regarding the navigation itself, the Hua Hum River offers a technical difficulty rated as Class II and III. This defines it as a “fun but safe” river, ideal for families with children or people trying rafting for the first time. The narrow canyon alternates between stretches of absolute peace and backwaters with rapids that inject just the right amount of excitement. Among the highlights of the descent are the “Rápido de la Terma,” famous for its calm waters that invite a group dip, the “Rápido de la Cabeza del Indio,” and the emblematic “Piedra Tumbadora.” In this final stretch, the guide’s skill and the rowers’ synchronization are put to the test to navigate rock formations and chutes that mark the climax of the adrenaline rush.

One of the most distinctive and exciting aspects of this journey is its international nature. Descending the Hua Hum takes rafters across the border into the Republic of Chile by water. The route ends at a bend in the river, just three kilometers before it flows into Lake Pirihueico, already in Chilean territory. Due to this border crossing, it is an essential requirement for all participants to carry their National Identity Document or passport, along with the corresponding authorizations for minors, as the return to San Martín de los Andes is done by land, passing through customs and immigration controls.

This journey represents much more than a sporting descent; it is a deep immersion into one of the wettest and most pristine corners of the continent, where the sound of the water and the majesty of the virgin jungle completely dominate the experience.