One of the most demanding hikes I’ve done in the Cusco region is the two day/one night hike to Quellcaya Glacier, the largest tropical glacier on the planet, in the Vilcanota Mountain Range, approximately five hours from Cusco.

Known locally as Quenamari, the glacier sits at 5,600 metres above sea level and serves as a critical water source for the Sibinacocha Lagoon and beyond. It feeds the Vilcamayo River, which becomes the Urubamba River that winds through the Sacred Valley towards Machu Picchu, and later the Ucayali River – itself a tributary of the mighty Amazon.

The glacier itself is striking, a vast, glaring expanse of ice stretching across the mountain. Standing there, the silence is profound, broken only by the occasional crack of shifting ice or the distant calls of Andean birds. It’s a scene I haven’t encountered anywhere else.

Beyond its geographical significance, the glacier holds deep cultural importance for the local Quechua communities, who continue to perform ancestral rituals in honour of Pachamama, or Mother Earth. Meeting the people who live in this extreme environment was fascinating. With the help of a guide to translate from Quechua, I was able to hear their stories—how they survive at this altitude, relying on alpaca herding, weaving, and a deep knowledge of their environment. The remoteness of their lives is difficult to comprehend; the nearest town is 40 kilometres away. Spending time with them was a real privilege

The surrounding landscape is every bit as remarkable as the glacier itself. The region is dotted with glacial lakes, peat bogs, and untouched high-altitude grasslands. I was particularly struck by the wildlife—there are vicuñas, llamas, and alpacas here, and, unexpectedly, frogs! In the Sibinacocha Lagoon, I saw more frogs than I’d imagined possible, their chorus filling the air as we set up camp in sub-zero temperatures. Some of these species are endangered, yet here they seemed abundant, thriving in the icy glacial waters.

Need to know

This trek is not for the casual hiker. It’s physically demanding, and the high altitude is a serious factor. Prior acclimatisation in Cusco (at least two days) is essential, and you need to be comfortable hiking for extended periods in sub-zero conditions. The final approach to the glacier involves a three-hour ascent at extreme elevation.

The only viable time to visit is during the dry season (April to October). Even then, weather in the Andes is unpredictable, and sudden rain or snow showers are always a possibility. Avalanches can be a risk in the wet season, making this trek unsafe from November to March. Essential gear includes warm, layered clothing, waterproof trekking trousers and boots, gloves, a hat, sunglasses, and high-SPF sun protection. Despite the cold, the high-altitude sun is intense. A headlamp is also necessary for early-morning trekking in low light.

Accommodation options include camping or a rustic lodge near the glacier. I camped on my visit, but after experiencing temperatures well below freezing, I’d strongly consider the lodge next time.

With the glacier retreating rapidly due to climate change, now is the time to witness this extraordinary natural phenomenon. This trek is challenging, but for those willing to step far beyond the usual tourist trails, it offers an experience that is both humbling and unforgettable.