Is this the world's most 'breathtaking' hike?

It is 10.23am on a sunny spring morning in Nepal's Sagarmatha National Park when I get my first close-up view of Mount Everest. Rounding a corner on a ridgeline at 3885 metres, after a two-hour shuffle uphill from Namche Bazaar - a Sherpa village ranged like an amphitheatre above a plunging ravine - there it is, the planet's most fabled mountain.

For much of the past century, since British mountaineer George Mallory died in 1924 trying to climb Everest "because it's there", Sagarmatha, as it is known locally, has represented the pinnacle of human endeavour. It is still only 71 years since Edmund Hillary and Tenzing Norgay became the first to reach the summit, and many more climbers have perished striving to emulate their feat.

So, simply to see it from up here, in wide angle, delivered as if through a Panavision anamorphic lens, is a privilege.

For an 8848-metre mountain, Sagarmatha is hard to pick out, at first. It is garlanded and partly obscured by wispy cloud, and clustered by other colossal peaks, including neighbouring Lhotse, and the characterful, broad-faced Ama Dablam in the foreground, sharply defined by the densely blue mountain sky.

For once, I can employ travel writing cliche in pronouncing the panorama "breathtaking", because at this altitude oxygen levels are low and, following our challenging climb, it's taking time to still my gasps for air.

Thirty years ago, when I was young and stupid, I believed I might one day climb Everest. A close shave in the Corsican mountains, when I nearly fell 2400 metres down a sheer rock face, put paid to that presumption.

Now, I'm suddenly in my sixties and, after decades traversing the planet for work, and a recent diagnosis with a spinal condition called DISH (Diffuse Idiopathic Skeletal Hyperostosis), should probably be putting my feet up on a Mediterranean cruise.

Yet it is this diagnosis that has prompted me to take on active adventures, like this World Expeditions trek, while I still can. This groundbreaking company began as Australian Himalayan Expeditions in 1975, offering guided trekking holidays in Nepal at a time when the region had little tourism or infrastructure. So next year marks a significant milestone, 50 years since those first guided walks in these iconic mountains - during which thousands of Aussies have trekked in Nepal - and a half-century of adventurous small-group tours around the world.

Over the past few months, I've prepared methodically for this trip marking that anniversary, doing regular training hikes, daily yoga, Pilates and even workouts in an Air Locker gym, in which oxygen and nitrogen levels are set to mimic conditions at altitude.

None of which helped me last night in my room in the comfortable Sherwi Khangba (Sherpa's home) lodge in Namche Bazaar. Struggling to breathe due to altitude and the day's rapid ascent, I barely slept and, at 6am, sought out tour leader Bir Singh Gurum, who has led Himalayan treks for World Expeditions for 25 years, to discuss my options.

"You can stay in Namche this morning," he advised, "and take a shorter route to our next eco-camp, later, you can go back down to acclimatise, or you can take Diamox to combat altitude sickness, and continue."

I swallow a Diamox (acetazolamide) tablet and for the next two hours trudge uphill, breathing like a steam engine, my pulse thumping in my ears. "Bistarai, bistarai," chirps World Expeditions' guide Bal Bahadur, BB for short, ahead of me, repeating the local trekking mantra "slowly, slowly" as he ambles up the steep mountainside, like a slow-motion Nepalese Fred Astaire.

With BB's encouragement, regular rests and the medication now taking effect, I reach that first vision of Sagarmatha, all the more fulfilling for being so hard won. From now on, as we track along the ridgeline, the views only improve and it is especially sublime to arrive, a little later, at the Everest View Hotel (built with Japanese funding in 1971) and take it all in from the terrace over a restorative pot of lemon, ginger and honey tea.

Our cohort of 10 trekkers, supported by 12 local staff including guides, cooks and porters, comprises seven Australians, two Canadians and a Kiwi, and ranges in age from 28 to 65. It has by now, after six days together, become a homogenous group with shared endeavour, humour and wonder at the scenery at its core.

Our Nepali guides, led by Bir Singh Gurum, remain unflaggingly dedicated, supportive and kind throughout our trek.

From when we meet, in Kathmandu at the Radisson Hotel, to when we return there 12 days later, this tour is seamlessly well organised, with Bir Singh providing information every evening about what's in store the following day, as well as background on Nepal's history and culture. A natural storyteller, one night he also shares the compelling tale of leading a trek through the epicentre of the country's devastating 2015 earthquake.

Our journey begins with a long bus ride from Kathmandu to Ramechhap, where there is a regional airport - a drive along the edges of deeply bowled valleys that is so bumpy, my Fitbit watch records me taking 21,500 steps on the way!

At Ramechhap we await an early-morning flight to Lukla, with its tiny 527-metre-long airstrip, carved into the Himalayan mountainside and on the rim of a cavernous ravine, considered one of the most dangerous in the world. Happily, with the morning cloud cover parting for just long enough, we bundle into the twin-engined plane, clutching our daypacks, and within 20 minutes are swooping safely into land.

Lukla, at 2850 metres, is the bookend to our trek in the Everest region. It is a busy mountain village where lodges, souvenir shops and bars abound and we encounter the first trains of donkeys and dzopkyo (a crossbred yak/cow) carrying heavy kerosene tanks and produce to the higher reaches.

Soon, we are taking our first steps on the trail, heading down towards the Dudh Kosi (Milk River), a glacial torrent that will be our near constant companion along our trek, and passing the first of innumerable "mani" boulders and walls, inscribed with devotional mantras.

The spiritual dimension to this Khumbu valley region is already clear, with Buddhist prayer flags in five colours - blue and white signifying sky and air, red representing fire, green symbolising water, and yellow the earth - arrayed around the trail and chortens (mini-stupas) a regular feature.

While Nepal is 81 per cent Hindu, it was the birthplace of Buddha, with both religions co-existing here for centuries, and these mountains are predominated by the Buddhist Sherpa or "east people", who originated in Tibet.

After an untaxing two-hour walk we reach our first eco-camp at Ghat, perched at 2530 metres' altitude, and settle in for our first night under canvas in the Himalayas. We wake to the sight of the snowy peaks of the nearby Karyolung range and are sent on our way by camp caretaker Gaga Maili (meaning "middle sister"), with kadas (holy scarves for luck) and a barrage of toothy giggles.

Our second day of trekking skirts the edge of a huge cleft valley, running through forests of Himalayan pine and past hillsides speckled by blossoming pinkish-red rhododendron bushes. We begin to see commercial porters bearing 100-kilo loads on their arched backs, strapped, for balance, across their foreheads. Their 2.5-day journey will earn them 7000 rupees ($78), putting our efforts, lugging light daypacks, into perspective.

Yet for one of our group, young French-Canadian Caroline, who is scared of heights, there are numerous daily challenges as we cross suspension bridges strung high above raging rivers, often rocking side to side with all the foot traffic, including pack animals. With courage and eyes fixed on the backpack of the person in front of her, she makes it across them all.

Our second mountain campground, is near Monjo, at 2840 metres, and we get in early enough for Bir Singh to lead us on what he calls a "short and sweet" hike above camp, allowing us to "walk high and sleep low", as per altitude-trekking advice.

Our third day's hike to Namche Bazaar is a demanding one, crossing a bridge swung high above the junction of two rivers, before ascending steeply in a series of switchbacks - which are designed to make the climb less arduous. Along the way we see our first pheasant, Nepal's national bird, and enter the World Heritage-listed Sagarmatha National Park, which encompasses eight peaks above 7000 metres and protects Sherpa and Buddhist heritage, and rare animals like the snow leopard and red panda.

Reaching Namche, once a small village with no electricity but now the Sherpa capital of the Khumbu region, we pause for a well-earned tea break, outside a cafe in the midday sun.

Our home for the night, a lodge run by 65-year-old Sherpa photographer Lhakpa Sonam and his family, offers luxuries such as hot showers - a bargain 500 rupees ($5), including towels - and ensuite toilets. It's an irony that this is where I suffer my bout of altitude sickness.

Within the lodge compound there is also an excellent Sherpa cultural museum, documenting the history and culture of these extraordinary mountain people and their role in opening up the world's tallest peaks to climbers.

It's the next morning, after my sleepless night, that I get a sense of what the final approaches to Everest might be like, on that breath-sucking shuffle uphill.

After stopping at the Everest View Hotel, we descend into Khumjung, that looks like an Outback mining town, where the "schoolhouse in the clouds", founded in 1961 by Edmund Hilary, is located. It now has 350 students from throughout the Khumbu region, who walk for hours to and from school, along high mountain passes.

For us, every incline conquered brings a greater sense of achievement and the higher we climb, the more dramatic become the settings for our eco-camps.

At Kyangjuma, our penultimate camp, we open our tent flaps to a panoply of jagged peaks, backlit by the sunrise. From here we drop down again to the Dudh Kosi valley, before climbing for 4.5 hours up the other side, through rhododendron forest.

Our reward is to arrive at Tengboche Monastery, the largest Buddhist gompa (compound) in the Khumbu region, set on a plateau with standout views of the Everest massif. It is home to 50 monks and an important stop for mountaineers, who request blessing here before tackling the world's highest peak.

After lunch, we continue on toward our final campsite, at Pangboche, its collection of green tents dwarfed and encircled by snow-covered peaks, extending in all directions.

We are now tantalisingly close to 4000 metres and so, following a rest, some of us take an additional hike beyond Pangboche's upper village. Leaden-legged after seven hours of trekking, standing among stupas, mani boulders and prayer flags, this is my proudest moment. A personal best height of 4032 metres.

We reboot over a Nepali dinner of dhal, potato curry and chicken, in the toasty dining room.

The the next morning we begin our return journey to Lukla under crystal-clear skies, allowing us to re-appreciate scenery we puffed through yesterday. While the long downhills of the next two days are easier than the ascent, they demand much of knees and a methodical pace, and at lunch today, beside the river, accumulated fatigue catches up with me.

Arriving back at Namche Bazaar, I've rarely felt so grateful for accommodation with a solid roof and hot showers. It is also lovely to return, next afternoon, to beaming greetings from Gaga Maili, at Ghat eco-camp, six days after we left her.

It is just two hours from Ghat back to Lukla, passing an onslaught of trekkers starting out in this region's peak season, and we spend the day here souvenir-hunting and celebrating in an Irish bar.

As we say goodbye to the majority of our Nepali support team, our cooks and porters returning down the valley to their families, I find myself moved to tears. There is still an early-morning flight to Ramechhap and drive back to Kathmandu to go, but this is the end of our trek and these are tears of weariness, accomplishment and, above all, gratitude.

It is important not to over-egg the difficulty of this World Expeditions' "comfort trek", which is perfectly designed and doable, with sensible preparation. However, for me, this has been an epic journey to the top of the world, and I will never forget the scale of the ranges we've trekked through, nor how connected I've felt to their power while in their midst.

6am: Wake-up call and a hot drink delivered to tents, followed by a bowl of warm water for washing.

7am: Breakfast, featuring porridge or cereal, toast and jam, eggs and pancakes. Boiled drinking water is provided to carry while trekking.

8am to lunchtime: Between two and seven hours trekking, ascending 1500 metres, incrementally, over four days.

1pm: Lunch, including salad, pizza or chapati, prepared by our travelling cooks.

Afternoon: Options to take a short "acclimatisation" hike, explore local villages or rest in camp.

4.30pm: Tea and biscuits, before another bowl of washing water arrives and we don warmer gear, as evening closes in.

With each dining area warmed by a stove, powered by yak/cow dung (preferred to wood as it doesn't contribute to deforestation), this is where we congregate before dinner.

6.30pm: Hearty dinner, carefully prepared to minimise gastro issues. Pumpkin soup with popcorn is one Himalayan staple, and warming broths often feature, along with dhal, pasta, rice, meat and vegetables. Trekking at altitude creates a near-boundless appetite, so desserts, including cake and custard, are guilt-free.

8pm: After a briefing, it's bedtime, some waking at 5am next day to capture the sun gradually illuminating the planet's most formidable mountains.

Explore more: worldexpeditions.com

The writer was a guest of World Expeditions.