Planetwalker: A Memoir of 22 Years of Walking and 17 Years of Silence by John Francis
When the struggle to save oil-soaked birds and restore blackened beaches left him feeling frustrated and helpless, John Francis decided to take a more fundamental and personal stand-he stopped using all forms of motorized transportation. Soon after embarking on this quest that would span two decades and two continents, the young man took a vow of silence that endured for 17 years.