Lago Greve (2024) - The lake that time forgot

Lago Greve: The Memory of Water

There are moments in Patagonia when time itself seems to dissolve. As the final echoes of the No Te Rindas ('Don't Give Up') - a bright yellow fishing boat that the captain had crafted years ago from the Guaitecas cypress that dot the flanks of Patagonian channels -faded away, José cast his gaze at the towering ice wall before us. “This is a journey from another era.”

Our expedition sought to unravel a geographical enigma, one that held significance not just for Chile, but for the world. Together with my companions, Spanish adventurer José Mijares and Chilean mountaineer Pablo Besser, we aimed to find a passage across the Pío XI Glacier, the largest in the Southern Hemisphere outside Antarctica. On the other side, we hoped to traverse Chile’s sixth-largest lake and the world’s fourth-largest proglacial lake; Lago Greve, a body of water twice the size of Paris and shrouded in mystery. To our knowledge, no one had ever crossed the Pío XI from its famous southern face to its unseen northern terminus, and Lago Greve itself had only been visited once in modern history.

Quicksands and Impenetrable Forests

Comprehending Lago Greve is a challenging exercise. Despite its vastness, the name is almost entirely unknown. Even the inhabitants of Puerto Edén, the nearest settlement, seemed unaware of the herculean lake hidden behind the mountains. Nestled deep within Chile’s largest national park, Bernardo O’Higgins, the lake's surface alone is the size of the average global protected area.

Reaching the lake required eight days of classic Patagonian toil, marked by impenetrable forests, treacherous quicksands, bogs, and long white days atop the Pío XI. Between the three of us, we carried nearly 150 kilos of food and equipment - enough to paddle, camp, traverse the glacier, and survive for three weeks. Slowly, we inched towards our first cache, exploring each step before returning for the rest of our gear.

Patagonia punishes every mistake. Pablo left one of his mountain boots in the cabin of the No Te Rindas, a lapse that condemned him to the pain and indignity of wearing crampons over a mismatched pair of a rubber boot and a hiking boot. José’s faith in an old pair of worn-out crampons cost him dearly as we ascended and descended the glacier’s crevasses and ridges. As for me, I entrusted my fate to a veteran packraft, only to discover a two-inch gash in the inflation valve upon reaching a lagoon midway to Greve. Desperate, we spent an entire day and night trying to seal the air leak with various tapes and glues, fearing that our expedition might end prematurely.

In a last-ditch effort, we stitched the rubber with needle and thread... and it worked! Throughout the long crossings on the lake, sometimes up to five kilometers facing the glaciers with all my gear aboard, I lived in constant dread of hearing the hiss of the tear reopening.

Anthropogenic histories

Nearly a hundred years ago to the day, in November 1924, in this infinitely wild confine of Patagonia, an improbable Norwegian settler chose a valley of grasslands and ancient moraines to establish a sheep farm. The following year, he returned, building three small houses, shearing sheds, and a wool depot, and bringing in around two hundred sheep, along with some horses and cattle.

But the Norwegian’s venture, chronicled by Alberto de Agostini in his famous book Andes Patagónicos, was doomed to fail. After a harsh winter that decimated his farm with snow and starvation, the imposing glacier tongue that had lain dormant in front of his estate began to surge forward, advancing at a rate of up to 20 meters per day, crushing his farm before crossing the valley in a matter of weeks. The Norwegian escaped, but according to De Agostini, he left his livestock to the mercy of the Kawésqar nomads, and his dreams were buried beneath the glacier.

That glacier was the Pío XI, and the natural dam it formed created Lago Greve. Little is known about the Norwegian, but a few weeks before our expedition, we stumbled upon a clue. In the Spanish edition of De Agostini’s book, he is given the name Samsing. But on rereading the book another countless time, I noticed a footnote indicating that the Italian version gave his full name: Finn Samsing. Within days, we discovered marriage records in Punta Arenas for a Finn Samsing a few years after the disaster, and in 1944, a record of his death. Together with Camilo Rada, a renowned explorer, geographer, and archivist of Patagonia, we traced his descendants, piecing together a forgotten story of adventure, tragedy, and true exploration.

The Lake That Almost Wasn’t

As we traversed the Pío XI, we witnessed the landscape’s relentless dynamism. At one point, we came across an area littered with shells mixed into the mud, 50 meters above sea level, likely dragged and deposited by the glacier. A hundred-meter-wide swath of destroyed trees - massive trunks snapped in two like matchsticks - lined the glacier's path, strewn across dense, dark mud. When we reached the lagoon midway between the northern and southern termini, we saw the same phenomenon, with trees dragged and shattered up to 60 meters above the lagoon's surface and truck-sized icebergs marooned in the mud at the lagoon’s bottom. We concluded that a catastrophic flood had occurred recently; even the icebergs hadn’t had time to melt.

It was from above this lagoon that we first glimpsed Lago Greve on the horizon. It wouldn’t be a lie to say that there was an element of surprise and relief in seeing that the Greve was still there - perhaps due to the uncertainty of its existence, but more so because Lago Greve has long flirted with its own disappearance.

In 2022, a team of glaciologists in Japan was studying satellite images of Lago Greve. To their astonishment, they discovered that a flood of historic proportions had occurred at Lago Greve over a few days in April 2020. Almost overnight, the 240-square-kilometer lake dropped 18 meters, spilling the equivalent of 640 Giza pyramids-worth of water through a narrow, remote valley to the north. In what they judged to be one of the largest glacial lake outburst floods (GLOF) in history, no one noticed - until they did, two full years later.

The Most Complete Exploration of Lago Greve to date

The euphoria of reaching Lago Greve after eight days of hardship and adventure and seven years of planning, preparation, and countless delays, was unparalleled. We spent our first night under a sky ablaze with stars, beside the massive turrets of creaking ice formed by the Pío XI. Around us, an ancient forest of coihues - inundated during the lake’s formation a century ago - loomed menacingly over our tent.

For seven days, we circumnavigated much of the lake. We crossed five kilometers in front of the northern terminus of Pío XI, then skirted the southern shore. Uder the gaze of the imposing Volcán Lautaro, the highest peak of the Southern Ice Field and from which the Lautaro Glacier descends into Greve’s waters, we hugged the forests and waterfalls that cascaded together into the silvery waters. We explored Laguna Sor Teresa, with its multiple tributaries, and the two fronts of the giant Greve Glacier. The days passed in a zigzag among icebergs, marveling at the vertical forests and contemplating the pale high-water mark left by the 2020 flood.

A Garden of (Puerto) Eden

There were moments at Lago Greve when nothing would have surprised us. The isolation and inaccessibility of the place, coupled with its vast scale, could conceal a thousand mysteries. More than once, I found myself exploring rocky formations with crevices and small caves in the hills, hoping to find some trace of a previous human visit. It’s highly likely that, before the Pío XI closed off the passage, the lake and the green meadows encountered by Finn Samsing might have been valued as a hunting ground by the Kawésqar nomads. Not even the oldest members of the Puerto Edén community, whom I’ve had the privilege of knowing since my student days as an anthropologist, were aware of the lake’s existence.

In contrast, Greve Lake is a Garden of Eden for other species. After following a brown smudge through a small grove of cypress and taiques, I was able to admire a beautiful huemul deer (Hippocamelus bisulcus) against the backdrop of Volcán and Glacier Lautaro. I watched her for nearly an hour, as she occasionally cast a puzzled glance my way. In the following days, we spotted another pair of huemules and found countless tracks on the lake’s beaches.

Lake Greve, despite its remoteness and obscurity, is a natural treasure of inexplicable beauty, biological richness, and cultural heritage. Yet, despite its seclusion and anonymity, it is not immune to the threats posed by a world in constant flux. Many of its glaciers have shown alarming signs of retreat in recent years; we camped on shores that, in our satellite images, still appeared under the ice. Little information exists to monitor the state of Greve Lake’s glaciers and the vast ecosystem of which they form a part.

The Memory of Water

Our exploration of Lake Greve was a journey to an uncharted corner of the world; án immersion into a land suspended in a perpetual present, shaped by a unique glacier that advances and a lake that flirts with disappearance - two rebels against reality. The experience kindled within us a peculiar reverence for the Norwegian settler, lost to history, who breathed the same air and endured the same cold humidity a century ago, perhaps under the same perpetually bewildered gaze of animals unfamiliar with the human form.

Throughout the expedition, we adopted that quintessential Patagonian resilience, enduring conditions and challenges that seemed insurmountable, in pursuit of a fleeting and deeply personal dream, in a constant present dictated by an omnipotent nature. José was right, it would seem, when he murmured his first words of the expedition: this was indeed a journey from another era.