Laguna Charquini

The trek to Laguna Charquini — also known as Laguna Esmeralda — out of La Paz shows you nothing for almost two hours, and then the water arrives all at once: a dense, opaque turquoise unlike any other lake in the range, wedged between Charquini and Huayna Potosí. At around 5,000 metres the light comes down direct, unfiltered, with no dust in between, and the contrast between that water and the dark rock holding it in is so sharp it is hard to believe while you are looking at it. Nobody says much for the first few minutes.

That turquoise has a less comfortable explanation than you would expect: the lagoon has not always been there. It formed as the Charquini glacier melted — the glacier is losing close to a metre of thickness a year, and the projections have it gone by 2050. When you sit down beside the water, you are looking at ice that stopped being ice. That takes nothing away from it: it puts a date on it.

But first you have to climb, and the climb starts far lower down. The vehicle gains height fast and stops at the Club Andino refuge (~5,250 m), where coca tea is served before you carry on. It is the last break under a roof all day, and it is worth taking slowly: everything after this is open sky. At around 4,750 metres the road ends and the trail begins, on a bare stone altiplano where almost nothing grows. It is cold even when the sun is hitting hard, because at this altitude the two things sit together without contradiction: your skin burns and your hands stay cold.

Climbing is hard work, and it is worth saying plainly: this is not a technical walk — no ropes, no crampons, no mountaineering experience required — but it is demanding, and the reason is the air. Above 4,700 metres your body does twice the work for every step. You will stop more often than you planned, and each stop will last a little longer than the last. That is fine: every stop hands you back the whole cordillera — hanging glaciers, bare rock, Huayna Potosí and its 6,088 metres taking up half the view and, between June and September, when the altiplano dries out and the sky clears, Illimani in the distance at 6,438, the highest peak in the Cordillera Real. The final stretch, though, shows you nothing: you climb a slope of loose stone with your eyes on your own boots, counting steps, with no hint of what is coming. And then you top out. And the turquoise is there, all of it, exactly where a second earlier there was nothing.

Then you sit down by the shore, legs heavy, breathing still high, and the other thing arrives: a silence with texture, made of wind between the stones and nothing else. Nobody proposes anything, nobody hurries anybody; you stay sitting a long while, looking at the water and at the ridge of Charquini above it, and up here the cold starts coming in through your back before you notice. The city is less than an hour away and could be on another continent. That stretch of sitting — not the summit, not the photo, the sitting — is what people take home from Laguna Charquini. Going down is a different matter: within an hour the air works again, your legs remember how to walk fast, and the lagoon stays up there, where it was.

Before you book: a minimum of 48 h acclimatising in La Paz is required (condition of sale). This is a non-technical high-altitude walk — no ropes, no crampons, no mountaineering experience — but a demanding one, because of the effort and the altitude; no mountain equipment is provided. Not suitable during pregnancy, or with heart problems or high blood pressure, significant vertigo or very limited fitness, and not for young children. At any sign of feeling unwell, we descend immediately to lower altitude, towards La Paz.

Rates per person — from USD 52.

Would you rather reach 5,000 m by vehicle, with only a short walk? See Chacaltaya (5,421 m)