Growing up in Switzerland, Sarah Marquis had never heard of solo extreme walking, but by age 17, she was walking across continents by herself. Now 42, she’s an explorer for National Geographic. Her new book, "Wild by Nature" is about one of her most extreme journeys from Siberia, all the way to Australia. Vinita Nair spoke to Marquis about her journeys at the New York's famed Explorers Club.
