17年間，他為追求環保理想一直保持“噤聲”狀態；17年後，依然是為推進環保事業，他重新開口說話，去世界各地發錶演講。他，就是美國聖弗朗西斯科(舊金山)的環保鬥士———約翰·弗朗西斯。

Even more difficult for me to understand is the burgeoning feeling of something spiritual and sacred in the ordinary act of walking. I start to feel that each step taken is part of an invisible journey, for which there is no map and few road signs. I am not sure I am prepared, and the discomfort both frightens and excites me. In 1971, after witnessing an oil spill in San Francisco Bay, John Francis gives up motorized transportation and starts walking. A few months later, he takes a vow of silence that last 17 years. Through his silence and walking, he learns how to listen and his pilgrimage begins. Planetwalker is the inspirational and engaging story of one man's silent walk across America to raise environmental consciousness and promote world peace. Born the son of a West Indian immigrant in north Philadelphia, John overcomes seemingly insurmountable obstacles on his walk from the California coast to the New Jersey shore. In silence, he earns a college degree and begins walking through the West to America's heartland where he earns a Ph.D. in land resources. When he reaches the East Coast, the United Nations Environment Programme names him a Goodwill Ambassador and the US government recruits him to write oil spill regulations following the Exxon Valdez disaster. Chronicling a young man's call to public service, Planetwalker addresses complex issues of environmental and social justice in America. It encompasses both John's interior journey as he confronts questions of life and death as well as his experiences of life on the road. John encounters people of all walks of life who illuminate the social and physical geography of his journey from the kindness of an Idaho rancher who leaves jugs of water for him on desert roads to the racist violence of an off duty deputy sheriff, who puts a gun to his head. We grow with John as he develops the qualities of character that give him the will and courage of his conviction to act on the deepest voice within him and allow his destiny to unfold. Along with John's haikus, watercolors and drawings, Planetwalker is filled with practical ways in which we too can become earth stewards and take our own pilgrimages both great and small. And as we discover with John on his extraordinary walk, pilgrimage can lead to knowing our kinship with all of life and the all embracing goodwill that unfolds from that realization. John Francis lives in Point Reyes Station, California with his wife and son. He is the founder and director of Planetwalk, a non-profit environmental education program. He travels around the world speaking on pilgrimage and change and is developing Planetlines, an environmental studies curriculum based on the walking pilgrimage for high schools and universities. This is his first book.