Guardian of the Wilderness (1976)

Based on the life of Galen Clark, whose determined efforts led to the creation of Yosemite National Park. When he is diagnosed with terminal tuberculosis, and disappointed that he hasn't accomplished anything significant with his life, Clark decides to vanish into the California mountains to die. But after surviving a series of perilous misadventures, including a heartening encounter with famed explorer John Muir, he regains his spirit. Newly inspired, he launches a courageous battle against the aggressive lumber companies threatening to cut down the rare and precious forest of giant Sequoias. His fight to save the wilderness takes him first to Sacramento, and then Washington, D.C. where he convinces President Abraham Lincoln to declare Yosemite the first public land grant, paving the way for creation of the National Park System.