A Swiss explorer spent three wild years walking 10,000 miles from Siberia to Australia - by herself.
She hauled nearly 70 pounds of gear on the journey, which sent her directly into the path of wild animals, extreme weather and drug dealers armed with automatic weapons.
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The fact that Swiss explorer Sarah Marquis succeeded in her long, wild trek seems remarkable given the number of close calls she encountered along the way.
Marquis was born an adventurer. "Even when I was a little girl, I was always taking off, sleeping in a cave with my dog overnight," she told espnW's Laura Marcinek recently. As a teenager she crossed the Central Anatolia Region in Turkey on horseback despite not knowing how to ride, her website says.
Her 10,000-mile, 1,000-day journey required extensive preparation. She spent two years working her way up to it mentally and physically, gradually increasing the weight she could comfortably carry on her back until her pack reached 66 pounds. Her distances on the trail got longer and longer as well, she told espnW.
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Early on, a tooth infection prompted evacuation from the Gobi Desert. When she resumed her trek, Marquis faced negative 31 degrees Fahrenheit temperatures and deadly blizzards. Drunken horsemen wreaked havoc on her campsite in Mongolia. She shared the Australian wilderness with crocodiles, venomous snakes and buffaloes. Her tent got wrecked repeatedly by sandstorms, hail and mudslides.
In the Laos jungle, weakened by dengue fever, Marquis made the mistake of pitching her tent near a pond. Usually she avoided that because water tends to attract snakes, and they in turn attract wild animals.
This time, the pond was being used by drug dealers. The armed men tried to lift her tent up while she was still in it. She got out, yelled, and one man shot his gun into the air, she recounted to Marcinek.
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That was the only moment Marquis considered hitting the red button on her tracking device -- not to get help, but because she wanted her body to be found. She got out alive by using her handy dictionary and staying calm for several hours.
"I never carry any firearm," Marquis told espnW. For her, carrying one would be an illusion of security. "If you're too secure, then you won't do the right thing regarding your own safety," she added.
That perspective reminded me of Isabella Bird, an intrepid British explorer who traveled solo through the Rocky Mountains in the early 1870s. It truly was the Wild West.
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"I once gave an unwary promise that I would not travel alone in Colorado unarmed," Bird wrote in her book "A Lady's Life in the Rocky Mountains." "I left Estes Park with a Sharp's revolver loaded with ball cartridge in my pocket, which has been the plague of my life." The revolver caught on her riding dress, children thought it's a toy, and the one time she slept with it under her pillow, Bird awoke the next day regretting her fear.
Last June, a helicopter dropped off Marquis in the wild, sparsely populated Kimberley region of Western Australia. Her National Geographic expedition involved walking 500 miles and surviving off the land for three months.
Her experiences reminded me at times of Robyn Davidson's 1,700-mile journey with camels across the western Australia desert in 1977, detailed in her book "Tracks." Over the past two decades, Marquis has essentially walked the world on foot, covering more than 10,000 miles.
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I've noticed that one of first the questions often posed to solo female explorers is, "Why?" Whether intentional or not, that can have judgmental undertones. As in, "Why do this alone? Why on earth would you risk yourself like this? What could be so important? Are you crazy?"
Marquis had numerous issues with her safety, but so have scores of other explorers. Motivated by curiosity, seeking closer connections with nature, and seeing the world in a new way, experienced explorers make calculated risks. Along the way, they are brave and resilient. Because, as Marquis says, adventure is a state of mind.