In the remote valleys of British Columbia's Purcell Mountains, hiking comes with a shot of adrenaline.

The first thing I heard was a disconcerting huffing and puffing in the bushes followed by the crescendo of something large and heavy running through the undergrowth in our direction.

"Get back!" my guide, Jason Loree, yelled, drawing the bear spray from his holster like a sharpshooter in a Hollywood movie.

A bear's head appeared out of the foliage, took one look at us and promptly turned on its heel and ran. Crisis averted.

"Grizzly," said Loree, slipping the bear spray back into his rucksack. "Fortunately, no cubs."

I let out a sigh of relief, my panic subsiding as quickly as it had arisen.

Hiking is generally seen as a relatively tame pursuit, but in the remote valleys of British Columbia's Purcell Mountains it comes loaded with the thrills and spills of an adrenaline sport.

The first adventure had been getting there. I was staying at Purcell Mountain Lodge, an off-grid retreat located around 25 crow-flying kilometres west of Golden, a diminutive mountain town known for its skiing, whitewater rafting and mountain biking culture. Due to the rugged, precipitous terrain, the only way in is by helicopter, a 15-minute flight that swoops low over narrow mountain ridges and steep-sided valleys before precision landing on a gravel helipad the size of a small putting green.

Heli-hiking was "invented" in Western Canada in the 1970s, a summer off-shoot of heli-skiing that had been pioneered a decade earlier by Austrian Canadian mountaineer Hans Gmoser. Teaming up with Canadian geologist Art Patterson, Gmoser formed Canadian Mountain Holidays (CMH) and led the first heli-skiing adventures in British Columbia's Bugaboo Mountains, part of the Purcell Range, in 1965. It opened remote alpine areas to non-mountaineers, using helicopters to drop travellers into the wild, otherwise inaccessible terrain. The idea took off. Gmoser and his team built backcountry lodges and trained guides, and by 1978, summer heli-hiking trips were drawing travellers eager to walk through pristine alpine wilderness without the weeks of hard climbing.

Plan your trip:

Heli-hiking and heli-skiing trips can be booked directly through the Purcell Mountain Lodge. Packages include helicopter transfers, private rooms, chef-prepared meals and daily guided tours with ACMG guides. The departure point is Golden Airport. Golden sits on the Trans-Canada Highway 140km (87 miles) west of Banff and is served by comfortable daily Rider Express buses connecting to Vancouver in the west and Calgary in the east. The best in-town base is the Prestige Inn.

In the years since, heli-hiking has evolved from a little-understood niche activity to a well-curated adventure package with options to partake in alpine trail-running or fixed protection climbing on via ferratas using cables and ladders. Thanks to Gmoser's vision, there are now more than 30 lodges offering heli-hiking in British Columbia, from the Bugaboos to the Great Bear Rainforest.

I'd booked my four-day heli-hiking trip at Purcell Mountain Lodge a few weeks earlier without really knowing what to expect. Instructed to bring a sleeping bag, a towel and a 30-litre rucksack, I packed........

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