Patagonia O Circuit Guided Trek March 2027

The O Circuit offers an unforgettable multi-day trekking adventure through the heart of Patagonia. Incorporating the iconic "W" trek, this extended route also encircles the Paine Massif, leading trekkers into some of the park’s most remote and pristine wilderness, a true expedition for the adventurous and nature enthusiasts alike.

Highlights include the awe-inspiring Paine Towers, the dramatic Paine Horns, the breathtaking French Valley, the majestic Grey Glacier, Dickson Lake, Los Perros Glacier, and panoramic views of the Southern Patagonian Ice Field. Starting and ending in Puerto Natales, the trek covers approximately 130 km with a total elevation gain of 4,600 meters.

For those seeking a challenging and deeply rewarding experience, the O Circuit is a must-do.

View Map & Route guides page

PATGONIA GUIDED TREK GRADING – GRADE 3: DIFFICULT

Grade 3 treks are difficult and a good level of fitness is needed before you arrive. Good paced hiking carrying day sac plus more. Repeated seven-hour mountain days on mixed terrain with short breaks. No options for rest days. Difficult level of challenge due to the terrain and remote environment. Not an off-the-couch activity!

Our O Circuit trek spans 10 nights and 9 days, covering approximately 130 kilometers with a total elevation gain and descent of 4,600 meters. Starting and ending in Puerto Natales, this carefully planned itinerary allows for a full immersion into the raw beauty and rugged terrain of one of the world’s most iconic national parks.

The most challenging day of the trek is the stretch between Camp Los Perros and Refugio Grey, which crosses the formidable John Gardner Pass. This section involves a significant amount of distance, elevation gain, and descent, but it also delivers some of the most breathtaking scenery on the entire circuit. It's a tough day, but one that promises unforgettable rewards, you won’t be disappointed!

If, for any reason, you feel unable to complete the trek, it may be necessary to return to Puerto Natales … . Your safety is our top priority, and we’ll assist with all necessary arrangements to ensure you return comfortably and can rest and recover.

A guided trek offers expert navigation, in-depth local knowledge, group camaraderie, and an added layer of safety. All our treks are led by qualified UIMLA mountain professionals alongside experienced local guides who know the trails intimately. They prioritize your safety throughout the journey while enriching your experience with insights into the region’s flora, fauna, and cultural history along the O Circuit.

All of our worldwide treks are limited to a maximum of 8 clients, ensuring a more personal, supportive, and experience. The O Circuit trek is led by a highly qualified MBT UIMLA-certified guide, accompanied by an experienced local Chilean guide. A dedicated team of porters provides additional support, helping to carry your belongings so you can focus on enjoying the journey.

If you would like to check who else is booked on a guided trek, please just contact us. We can tell you the make-up of your group, the ratio of males to females and give you an idea of the group’s age profile.

Our guides are very experienced, fully qualified Mountain Leaders who live and work in the Alps all year round. They also work in other mountainous areas in the world and support our worldwide treks alongside the local guide.

UIMLA Qualification

The Union of International Mountain Leader Associations (UIMLA) (UIMLA) was founded in November 2004 and is an internationally recognised qualification that sets standards for mountain leaders all over the world.

Mountain Leader Associations

Mont Blanc Treks are affiliated to SNAM & BAIML the French & English Mountain Leader Association who are full members of the Union of International Mountain Leader Associations (UIMLA). They look after the professional interests of International Mountain Leaders in Europe & around the world.

UIMLA: Union of International Mountain Leader Associations

BAIML: British Association of International Mountain Leaders

SNAM: Accompagnateur en Montagne European

All our guides are certified in Wilderness and High Altitude First Aid, ensuring they are fully prepared to handle emergencies in remote and challenging environments.

You won’t need to carry all your gear during the guided trek, as we provide a porter service with a maximum weight allowance of 10 kg per person. You'll need a suitable daypack to carry your daily essentials—such as clothing, snacks, water, and any personal items you want with you on the trail. Your main luggage will be available each night during the trek. At the trek briefing, you'll receive a waterproof duffel bag to pack your essential items and extra clothing for the porters to carry.

There are no compulsory single supplements on our guided treks. Our accommodation is on a shared basis in twin rooms. This means that you are likely to share a room with someone else of the same sex and if possible a similar age. In the event that there is nobody suitable to share with, a single supplement will be charged towards the trek start date once we have final group details.

On our Patagonia guided trek, we use carefully selected, tried-and-tested lodges that provide comfort, warmth, and a welcoming atmosphere after a rewarding day in the mountains. We only work with places that we’d be happy to stay in ourselves — if it doesn’t meet our standards, we don’t use it.

View our Where to Stay Page

On the Patagonia guided trek breakfast is provided each morning, we will stop at a local guesthouse on the trail for lunch and a three-course evening meal is included on all nights whilst on the trek. Evening meals in …… and ….. are not included. Please refer to your specific trek itinerary for full details.

View our What to Eat Page

Essentials include:

• Hiking boots with ankle support

• Waterproof jacket and trousers

• Warm layers (fleece, down jacket)

• Trekking poles

• Daypack (25-30L)

• Hydration system (water bottles or hydration pack)

• Head torch, sunscreen, sunglasses

View our What to Bring page for more detailed information.

Yes, trekking poles are highly recommended for stability and reducing strain on descents.

We advise you to carry the basics, including plasters for blisters and pain killers for aches and muscle strains. (Don’t forget any of your usual medication). You will be able to replenish supplies along the routes in certain locations.

Once you have decided on your trek all you have to do is fill out our booking form, make the payment and get ready for an experience of a lifetime!

It is essential that you fill in all the relevant sections, so we have all the necessary information at the time of booking.

Once we have received the booking form and a deposit payment, we will confirm your booking and send you further information about the trek. To make the booking a simple process, we have explained all the methods of payment we accept. If you have any queries while booking your trek, do not hesitate to get in touch with us in Chamonix.

We recommend you take out cancellation insurance at the time of booking your trek. Should you need to cancel you will need to inform Mont Blanc Treks Ltd by email. If you cancel your trek the following conditions apply: 

• More than 12 weeks before trek start date - loss of deposit. 

• 6 – 12 weeks before trek start date - loss of 50% of the trek fee. 

• Less than 6 weeks before trek start date loss of 100% of the trek fee.

Yes, travel insurance covering trekking activities, medical emergencies, and trip cancellations is required.

Medical

Your own insurance is crucial. If you are on a guided tour, your guide will do their utmost to ensure your safety, but accidents can happen and even trivial accidents can result in a hefty bill if evacuation off the mountain or transport is involved. If you are unsure of your insurance cover, please ask us before the trek, rather than at the time when you may require assistance.

Possessions

Equipment can easily be lost or left behind on a trek and Mont Blanc Treks cannot be held responsible for your private possessions. During transfers, bags are left for collection and again after delivery, in some relatively public places within the hotels we use. Please make sure possessions, bags and equipment are adequately insured and kept safe. Suggestions for trekking insurance companies that have been used by previous clients are:

For residents worldwide: World Nomads, TravelEx 'Adventure Plus Pak', True Traveller

For residents in the UK: British Mountaineering Council, World first

For UK and EU residents: Globelink

For residents in the USA: TravelEx 'Adventure Plus Pak'

For residents in Australia: Insure4less

The easiest way to travel to Puerto Natales is via Santiago de Chile, you can take an internal flight that takes approx 3hrs 30mins. Currently LATAM and SKY operate into Puerto Natales airport. It is also possible to arrive by bus from Calafate in Argentina if you are visiting  this area beforehand. Although we don’t organise your travel to the start point of the trek we can give you advice so please feel free to ask.

Travel from the airport to your start hotel is up to you to arrange, the journey takes about 20 minutes. There are various options available, which include private taxi or public transport. The cost is not included in your holiday. Please ask for further information.