(CNN) — Kayla Milaudi will never forget the daunting feeling of looking out across the expansive, ancient Northern Territory landscape at sunrise from the peak of Mount Sonder, west of Alice Springs.
The 28-year-old from Melbourne was about to take on the biggest physical and mental challenge of her life.
The business banker had been woken at the Redbank Gorge at the startlingly early hour of 2 a.m. for her first day of the Larapinta Extreme Walk, beginning by scaling up the mountain with headlamps, water bottles and muesli bars in time for a dawn view.
From her lofty vantage point she realized the full scale of the challenge ahead: crossing grass plains in the heat of the day, navigating prehistoric boulders, hills and swollen rivers, all the while being on alert for possible poisonous snakes and scorpions.
It was going to take all the energy and determination she had over 11 days to walk 223 kilometers (138 miles) across the rugged land to the center of Alice Springs to raise money for the NPY Women's Council, an organization that aims to improve the lives of indigenous women and their families. "I sat up there in the freezing cold watching the sunrise in that vast land and it was a powerful eye-opener," Milaudi tells CNN Travel.
"It was serene but also somber as the full weight about what you're going to do feels very real for the first time."
Milaudi knew the walk, along with around 30 others, would involve hardship and most likely tears, no showers or phones, blisters and exhaustion. And it did.
But it would all be for a good cause -- so she's preparing to go through it all again when this year's trek sets off on May 15.
Trek helps future generations
Participants of the annual Larapinta Extreme Walk trek more than 200 kilometers in 11 days.
Tania Verbeeck/Larapinta Extreme Walk
The charity trek, which takes place over 11 days, ends each year on May 26 on National Sorry Day.
The annual event has been held for 20 years to remember the mistreatment of Australia's indigenous people.
In particular the day marks a remembrance of the "Stolen Generation," referring to six decades of Australian government policy that dictated Aboriginal children should be forcibly removed from their parents with the aim of assimilating them into the predominantly white population.
Each trekker pays a fee to take part and also has a sponsorship target of a minimum of $1,200 AUD ($907) each.
Last year they raised $100,000 AUD, which funds the annual Law & Culture meeting to empower indigenous women in the remote NPY (Ngaanyatjarra Pitjantjatjara Yankunytjatjara) region of Australia as well as other key NPY Women's Council initiatives.
Tony Messenger, who created and organizes the walk, tells CNN Travel the meetings in particular help give future generations of indigenous women a voice in society and exchange traditional knowledge that would otherwise be lost.
"The meetings really help strengthen younger women to their heritage and culture and also reunite friends and family," Messenger explains.
The trek, supported by a crew that organizes meals and tents, is purposely difficult, Messenger reveals.
"If it was easy nobody would get sponsors so it's planned as a real challenge and we give extensive advice about the training needed to get through it."
Trekkers are even sent a schedule of training that takes up hours of walking each day and at weekends.
Participants spend months preparing for the extreme walk.
Tania Verbeeck/Larapinta Extreme Walk
"It's an extremely hard walk," Messenger says. "Every year around 10% drop out because of injury and dehydration so the fitter you are coming into it the better."
Those new to the trek this year have been busily training for many months in preparation.
Kate Lyons, 44, from Sydney, has already raised nearly $10,000 AUD in sponsorship and is relishing the chance to "go off the grid" from her normal life.
"Luckily, I feel really prepared," says the mother-of-three, explaining how she was spending weekends walking coastal paths around Sydney harbor with supportive friends.
"I can't believe I can carry so much weight in my backpack and walk over 20 kilometers and feel OK at the end of it.
"It's a once-in-a-lifetime opportunity and my main aim is not to get an injury so I can enjoy every moment."
'Life-changing' for participants
Messenger says the trekkers all go through a similar pattern during the trek which he describes as "life-changing."
"First there is the initial pain and shock of the long days of walking and the niggles that come with it," he says.
"But then people go a bit quiet because without distractions of everyday life the brain starts to mull things over that you may have buried for years."
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After this stage of pensive self-reflection, the trekkers usually go through an emotional stage in the final days, Messenger says.
Milaudi, who has signed up again this year, agrees. She says during last year's walk she felt worn down by painful feet and ankles and wanted to reach the end as her parents were waiting to greet her.
"But I also felt a sense of sadness the experience was ending," she says.
Final day provokes tears
Kayla Milaudi, pictured, is about to set off on her second Larapinta Extreme Walk.
When the trekkers finally reach the Old Telegraph Station in Alice Springs on National Sorry Day what greets them often prompts tears.
Women who are directly helped by the fund-raising effort greet them and a celebration and afternoon tea takes place.
The station itself is particularly poignant as a tin dormitory on the property, dubbed the Bungalow, once housed Aboriginal children who had been forcibly removed from their families. In 1935 it was home to over 130 children.
"There is lots of hugging and tears," Messenger says, "It's the perfect end to an incredible challenge."
Andrea Mason, CEO of the NPY Women's Council, says the funds were greatly needed and the gatherings helped so many women.
"The gatherings are significant events for the NPY Women's Council as they provide an opportunity for senior women to exchange and affirm their traditional law and cultural knowledge and to teach younger female relatives," she says.
Mason describes how when the walkers make their way in to the Telegraph Station complex, the atmosphere is a celebratory one.
"Everyone greeting the walkers [is] cheering, waving flags and sometimes there are young people beating drums," she says.
"These sounds are all directed to the walkers and we do this to express our gratitude to them for laying down their time, resources, family time and their mental and physical well-being for the women of the NPY region.
"Often words can fail to express this deep gratitude, so on the last day, all of us who welcome them to the final stage just clap and shout our hearts out."