Nicknamed the “planet walker,” John Francis stopped riding in motorized vehicles for over 22 years beginning in the early 1970s because of the negative effect on the environment. During that time he walked the width of 48 states and walked to South America. He only returned to motorized transportation in 1994. He also took a 17-year vow of silence around the same time and was able to earn bachelor’s, master’s and doctorate degrees while being quiet. He was named a United Nations Environmental Program Goodwill ambassador in 1991 and wrote the book Planetwalker: How to Change Your World One Step at a Time, about his extensive experiences traveling by foot.