Described as “the best alpine trek in the world", this 170km of hard, exhilarating mountain walking is best experienced through the eyes of a local mountain guide.

Peru’s Cordillera Huayhuash has been called "the best alpine trek in the world". Fabled for being the source of the mighty Amazon and having peaks that soar snow-fluted above 6,600m, the Huayhuash is a compact range of 20 main mountains knotted together by blue glacier ice: a place of visual magnificence. A journey around the entire range is 170km of hard, exhilarating walking, where thin-air passes link jagged mountains, azure lakes and vast skies.

Until quite recently the dazzling summits of the Cordillera Huayhuash lived beyond most Peruvians’ – and visitors’ – horizons. There were only donkey paths for access, and this was the lawless hideout of bandits and Sendero Luminoso (Shining Path) guerrillas. As security and infrastructure improved, the circuit began enticing more trekkers and climbers. So perhaps the best way to uncover an authentic Huayhuash journey now is to make it a cultural experience as well, by coming here with local people and seeing it through their eyes.

Discover a human landscape
The Cordillera Huayhuash is not a national park, it is a peopled landscape. In the dryer months, farmers from villages on the edge of the Huayhuash bring their livestock to graze here. Each mountain community has its own commonly-owned land, and walkers are asked to pay for the right to camp and pasture their donkeys. Pay with grace and enjoy the chance to share local knowledge over a cup of tea when the fee-collector comes by.

Walk with locals
Trekking the Huayhuash with Peruvians will bring the landscape alive. They will tell you local names, like the beautiful Quechua meaning of Jirishanca (snowy hummingbird). They might recount pre-Inca Huayhuash legends or point out a whole pharmacy of medicinal plants. To really interact with people here, speaking a little bit of Spanish is essential.

Trek with donkeys
These beasts of burden are key to trekking in the Cordillera Huayhuash. Do as Peruvians do and let donkeys carry the load – so you can circuit the Huayhuash with only a day pack while the donkeys lug camping gear and supplies. Contract locals as arrieros (donkey drivers) who understand the essential art of load-strapping and the early morning chase for overnight wanderers.

Respect the mountains
Come here in the cold, dry season of May to September, when the locals do. It may be freezing at night (be prepared for temperatures down to -15C) but days are generally clear and dry. There is a risk of getting snow bound in high passes the rest of the year.

Make sure you go slow. The Huayhuash circuit route is mostly between 4,300 and 4,700m above sea level, with passes of just on 5,000m. Know the symptoms of altitude sickness (as mountain people do) and act on them. The high-altitude sun burns; buy a sombrero in a local village before you hit the mountains.

Work together
Minga was the Inca term for work for the common good – and the concept is still strong in the Andes. A sense of equality among all in a walking party enhances a trip. Make sure everyone helps cook, eats the same food (and plenty of it), laughs together, works together and walks together.

Take the paths less travelled
People who grew up herding animals here know every little dusty back trail in the Huayhuash. If you are fit and seeking true isolation, ask locals to take you off the main circuit route, on paths that lead even closer to the peaks and glaciers. A caveat: donkeys may not be able to join you, so be prepared to carry your gear.

Find a local guide
Ask around for a guide in the Huayhuash-edge villages of Llamac, Pocpa or Pacllon. You may even get to camp at your guide’s house while you get organised. If you are approaching the Huayhuash from the town of Huaraz, eschew the big agencies. Zarela at the trekkers’ and climbers’ hotel Casa de Zarela can put you in touch with guides who know these mountains better than anyone.

The article 'Walking the Cordillera Huayhuash' was published in partnership with Lonely Planet.