At Ascent Ready, we don’t build training plans from behind a desk. We get out and do the treks ourselves, then bring back what we learned. Our team walked the full 8-day O Circuit through Torres del Paine, and we spent months beforehand reading everything we could find to prepare. We still learned a pile of things on the trail that no guide had told us.
So here’s the short version, and the one thing we hope you take away: if you have the time and the legs for it, do the O, not just the W. The extra days that make up the “O” were the most memorable part of our whole time in the park. The solitude, the glacier views, the sense of earning something. We finished completely sure we’d made the right call. The rest of this is the day-by-day, plus everything we wish we’d known going in.
The O Circuit: quick facts
- Distance: around 110 km (68 miles)
- Time: 6 to 10 days (we took 8)
- Difficulty: Challenging. Steep climbs, uneven terrain, and weather that changes by the hour.
- Start/End: the visitor center in the Las Torres sector, a short shuttle ride from the Laguna Amarga ranger station
- Season: November to March
Update, October 2026: the O Circuit has new rules
On November 17, 2025, five trekkers died in a blizzard on John Gardner Pass (1,241 meters), the high point of the O. CONAF reopened the circuit on December 9, 2025 with a cap of 100 visitors a day, one way travel only, and mandatory registration at the Coirón ranger station. Park entry changed on May 1, 2026 to a daily ticket or a multi day pass valid for 2 to 10 days, sold online only at pasesparques.cl. We walked the O before any of this, so check the current rules before you book.
Note: prices, fees, and check-in rules in Patagonia change often and some payments are cash only. We walked this during the 2024 season, so treat the logistics below as a guide and confirm current prices and check-in rules when you book.
What we’d tell you before you go
If you read nothing else, read this. These are the lessons that cost us time, comfort, or a few anxious moments on the trail.
- Book everything, and carry your bookings. Campsites are reserved in advance, and there are checkpoints. If you don’t have the required reservation, they will turn you around and send you back the way you came. This is not a place to wing it.
- Take a slightly later bus from Puerto Natales. We caught the early one and spent a long time in the shuttle line, then arrived before camp check-in even opened. A later start would have skipped both.
- The O side has rental tents available. Several O campsites had spare tents and pads to rent, which made last-minute changes possible. Don’t count on that flexibility on the busier W side, where you’ll likely pay a premium if you can change at all.
- One trekking pole, minimum. The descent from the Torres viewpoint is steep and slippery with loose gravel. A pole makes it safer and a lot kinder on your knees.
- Order food early at the busy camps. At Chileno, meals and snacks sold out by the time we got back from the towers, thanks to the day-hiker crowds. Put your order in early.
- Pick a sheltered tent spot. The wind in this park is no joke, especially above the tree line. A spot among the trees is worth hunting for.
- Download offline maps. Trail forks aren’t always obvious. An offline map app kept us on the right path more than once.
One of us carried a 35 pound pack for all 8 days and paid for it after the trek, not during it. The full story is in Training With a Heavy Pack.
Day 1: Park entrance to Serón
Our adventure started with an early bus out of Puerto Natales and a wait for the shuttle into the park. The trailhead wasn’t obvious from the visitor center, but keeping right put us on the path to Serón.
It was a modest day on paper, around 13 km in roughly 4 hours, but it felt surprisingly hard. Partly the trail forks, mostly the shock of a full pack loaded with eight days of food. The scenery was pretty, though it would be outclassed many times over in the days ahead.
Serón had hot showers and paid Wi-Fi, but limited cooking facilities and a stiff night wind, so a sheltered tent spot mattered. Check-in here is early afternoon, so there’s no rush to arrive at dawn.
Highlights: The Río Paine valley views. Challenges: The shuttle line, and getting used to a heavy pack.
Day 2: Serón to Dickson
Day 2 opened on mostly flat ground before a short, steep pass where the wind hit hard and stayed with us above the tree line. A checkpoint halfway through checked our reservations. This is where they turn people back if the booking isn’t there.
From the pass it was a flat 10 km into Dickson, with snow-capped peaks and the first glimpses of the towers. The descent into camp, with the lake spread out below, was a genuine moment.
Dickson turned out to be one of our favorite camps. Lively, well-stocked, hot showers, and far more shelter than Serón, especially among the trees.
Highlights: The flat, scenic second half and the mountain views. Challenges: The early pass and the relentless wind.
Day 3: Dickson to Los Perros
A 12 km day that started with a string of climbs before leveling out. It has a reputation as an “easy” day, but the distance still felt real. The last couple of kilometers were the payoff: a bridge crossing with the first view of the Los Perros glacier.
Los Perros was the most basic camp of the trip. No food for sale beyond prebooked meals, no Wi-Fi, and noticeably colder. With an alpine start coming the next morning, we rented a tent and pads rather than fuss with our own gear in the dark. Being able to do that at all is one of the quiet advantages of the O side.
Highlights: The Los Perros glacier. Challenges: The climb out of Dickson.
Day 4: Los Perros to Grey, over the John Gardner Pass
This is the big one, and the day that sums up why the O is worth it.
We were up at 4:30 am (not by choice, thanks to camp noise) and hiking by 6. The path to the pass was muddy and crossed on logs, made trickier by doing it in the dark with headlamps. The climb itself, full of switchbacks and exposed, windy stretches, wasn’t as brutal as we’d feared, though there were moments it felt like the top would never come.
We reached the pass around 8:30 am, and the view stopped us cold. The Grey Glacier sprawled out below, enormous and silent. We spent twenty minutes up there just taking it in. This is the view you earn by climbing the pass, and it is the single best argument for choosing the O over the W. We were lucky with the weather too. It could just as easily have been rain, hail, or screaming wind. We got sunshine.
Then came the reckoning: a long, steep descent that punished our knees. Three suspension bridges, a sharp climb after the first, and a few sketchy drop-offs that demanded full attention. Somewhere after the second bridge we met day trekkers coming the other way, the first new faces in four days. By the time we reached Grey camp, almost 8 hours later, we had never been happier to drop our packs.
Grey was well-equipped, with hot showers, a stocked store, and a beautiful beach on Grey Lake a short walk from camp. We watched the sunset there.
Highlights: The Grey Glacier from the top of the pass. Hard to overstate it. Challenges: The pass itself, and a steep, knee-grinding descent.
Days 5 and 6: Grey to Paine Grande to Los Cuernos
These middle days are where the O folds back into the more traveled W, and the trail gets busier.
The walk to Paine Grande was shorter and gentler, with last looks back at Grey Glacier. The catch is the lack of shade across open terrain, so sun cover and sunscreen earn their place in your pack. Paine Grande had the biggest kitchen and dining setup we’d seen, plus a store and bar, and a steady churn of people, since this is where many W trekkers catch the ferry.
From there toward Los Cuernos, rain rolled in. We’d planned to stay at Francis and visit the Mirador Británico, but the weather killed that plan and left us at camp far too early, so we pushed on an extra 5 km to Los Cuernos. The reward was the walk itself: stunning views of Lake Nordenskjöld and a rocky beach path that’s perfect for a snack stop. Los Cuernos had a cozy, ski-lodge feel, beer on tap, and views of the Cuernos del Paine with a waterfall behind. The facilities were a little worn, but the hot water was reliable, and it ended up one of our favorite camps.
Highlights: The lake views on the way to Los Cuernos. Challenges: Rain, mud, and shadeless open stretches.
Day 7: Los Cuernos to Chileno, and up to the Towers
A varied day. Gentle ups and downs to the Chileno fork, then a much steeper grind once you turn toward Chileno, made harder by full packs.
Chileno was the busiest camp of the whole trip, packed with day hikers and people in for drinks. Lesson learned the hard way: order food early, because by the time we came down from the towers, the meals and snacks were gone. There were no lockers either, so we secured our bags as best we could before heading up.
We’d hoped for a sunrise hike to the towers, but the weather pushed us to go in the afternoon instead, which meant crowds in both directions. To go up in the afternoon you have to leave Chileno before 2 pm, or you’ll be turned back at the checkpoint a few kilometers in.
The climb to the Mirador de Los Torres was the most congested stretch of our entire trek, steep and windy, with a descent made nervy by slippery gravel. This is exactly where a trekking pole earns its keep. But the towers themselves, rising over the lagoon, were worth every step.
Highlights: Lake Nordenskjöld, and finally standing at the Mirador de Los Torres. Challenges: Steep climbs, a slippery descent, and afternoon crowds.
Day 8: Chileno to the visitor center
A gentle finish. A short incline out of Chileno, then downhill nearly all the way to the visitor center in time for the afternoon shuttle. About an hour and a half of walking, mostly descending, so it’s one last test for tired knees, with a steady stream of fresh hikers heading up as we headed out.
And just like that, the O was done.
Highlights: Finishing the O Circuit, and the views leaving Chileno. Challenges: A descent-heavy walk on worn-out legs.
Would we do it again? In a heartbeat.
The W is a beautiful trek, and there’s no shame in choosing it. But the O gave us the quiet days, the glacier-topped pass, and the feeling of having walked a full loop through one of the most dramatic landscapes on earth. If your schedule and your fitness allow for it, take the extra days.
And on that last point: the O asks a lot of your legs. The passes, the back-to-back days, the descents that go on far longer than the climbs. The people who enjoy it are the ones who showed up ready for it. That’s the whole reason we do what we do.
