Polly Letofsky is the only woman to have walked across the world. She started in 1999 and took over five years. She tells, in an amazing interview, how you need to walk across at least four continents, cover at least 14,000 miles, and get signatures along the way of people who see you walk every day. She got into the Guinness Book of World Records but her own personal motivation was “to discover the world and how it ticks, and the people.”