Three granite towers above a glacial lake, in a park where the wind is the main character and every bed for the trek is booked a year ahead.
What it is
A national park of about 1,800 square kilometres in Chilean Patagonia, dominated by the Paine massif — a granite intrusion pushed up through sedimentary rock and then carved by glaciers into the three vertical Torres and the horned Cuernos.
Around it: turquoise glacial lakes, the Grey Glacier calving into its own lake, guanaco, condors and a small and genuinely present puma population.
The two treks
The W, four to five days, about 80km, tracing the shape of a W into and out of three valleys: the base of the Torres, the French Valley, and Grey Glacier. It covers the highlights and is the one most people do.
The O, eight to nine days, about 130km, the full circuit around the massif with the W as its southern half. The back section is remote, quieter and includes the John Garner Pass, which is the hardest day and the best.
Both are hut-and-campsite treks: you sleep in refugios or at designated campsites, and wild camping is prohibited.
The booking problem
This is the thing to understand before anything else.
Accommodation inside the park is run by CONAF (free campsites) and two private concessionaires (Vertice and Las Torres), and the O circuit crosses all three. You must book every night separately, with the right operator, in the right direction — the O is walked anticlockwise only — and the park entrance will refuse you without proof.
Bookings open around a year in advance and the December–February dates go within days. Nothing else in this guide has a booking window like it.
The wind
Patagonian wind is not a detail. Sustained 60–80km/h with gusts over 100 is normal in summer, and it comes off the ice field with nothing in the way. It knocks people over on exposed sections, and it destroys tents that were not designed for it.
Practical consequences: a properly guyed, low-profile tent if camping; trekking poles; a windproof shell rather than an insulated coat; and accepting that a planned crossing may be closed on the day.
Seasons
December to February is high summer: long daylight, the warmest temperatures, and the most people and highest prices.
November and March are the shoulders — fewer people, more changeable weather, and the best chance of the towers without a queue at dawn.
April to October is winter. The circuits close, though guided winter trips into the front country run.
If you cannot get a booking
Day hikes from the park entrances need no accommodation booking: the Base de las Torres hike is a hard nine-hour return day and delivers the single best view in the park.
El Chaltén in Argentina, four hours away, has free, unbookable, equally spectacular day walks to Fitz Roy and Cerro Torre, and many people prefer it.
Practical
Puerto Natales is the base town: gear hire, supermarkets, and the mandatory pre-trek briefing that several operators run.
Cooking is only permitted in designated shelters. Fire has destroyed large parts of this park twice, both times started by trekkers, and the rules are enforced without sympathy.
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