The Wind River Range in western Wyoming is the state's largest mountain range, nearly one hundred miles from north to south. With dozes of massive peaks, it is also home to the wildest country in the lower 48 states. Much of it is protected in wilderness, which David and his team commemorate on the 50th anniversary of the passage of the Wilderness Act of 1964. On arriving, they visit ancient foothill sites where Shoshone Indians left examples of their art, historic locations of Indian battles, and scars of mines and ghost towns before plunging deep into the wilds of the Wind Rivers - on foot.