Outings and excursions · El Calafate
Viedma Glacier: boat trip from Bahía Túnel and ice trekking
Photos: Liam Quinn · CC BY-SA 2.0 / Liam Quinn · CC BY-SA 2.0 / Fredlyfish4 · CC BY-SA 4.0 (Wikimedia Commons)
From Bahía Túnel, near El Chaltén, boats cross Lake Viedma to the front of the largest glacier in Los Glaciares National Park, its ice streaked with volcanic ash.
Eighteen kilometers from El Chaltén, on the shore of Lake Viedma, lies Bahía Túnel, the small port where boats leave for the glacier. As soon as you pull away from the dock, the lake shows its milky color and its scale: according to measurements by Argentina's CONICET, it runs deeper than 900 meters in places, making it the deepest lake in the Americas.
The boat heads west, past icebergs broken off the front and shorelines of rock polished by ice. Then the Viedma Glacier comes into view, the largest in Los Glaciares National Park: it covers about 977 km², flows down from the Southern Patagonian Ice Field through a canyon between Cerro Huemul and Cerro Puntudo, and ends in the water with a front some 2 kilometers wide and walls around 50 meters high.
Up close you notice what sets it apart from other glaciers in the area: dark stripes run through the ice. They are bands of ash from old eruptions of the Lautaro volcano, trapped in the layers and now drawing grey veins across the blue.
You also see time at work. CONICET researchers found that the front has retreated about 2 kilometers since 2014, and that instability has changed the way people visit: for years there was a crampon walk on the ice, combining the boat trip with a route among crevasses and ice ridges, but whether it runs depends on the glacier's condition each season. The boat trip, meanwhile, lets you take in the front from the lake and land on nearby rocky shores.
Although the excursion is listed among the outings around El Calafate, the gateway is El Chaltén, so it's best to plan the day from there and pair it with the hikes around town.
- Tour type: Scenic boat trip, with an ice-trekking option depending on the season
- Difficulty level: Easy (boat trip); moderate (glacier trek, when available)
- Tip: Before booking, check whether the ice walk is running that season; bring warm, waterproof layers, since wind and cold feel stronger out on the lake.
