Guardian of the Wilderness is a 1976 theatrical narrative film directed by David O'Malley about the true story of Galen Clark, an explorer who successfully campaigned to have the Yosemite area set aside from commercial development, the original forerunner of the American national parks system. Clark was prompted by his dedication to preserving places like the Mariposa Grove of Giant Sequoias, which he discovered, from being destroyed by loggers. The cast features Denver Pyle as Galen Clark, John Dehner as legendary naturalist John Muir and Ford Rainey as Abraham Lincoln. Clark was eventually appointed Superintendent of Yosemite, a position in which he served for more than two decades during which he defined the concept of an American park ranger; his varied history with the valley ranged across 55 years.

Mariposa Grove is a sequoia grove located near Wawona, California, United States, in the southernmost part of Yosemite National Park. It is the largest grove of giant sequoias in the park, with several hundred mature examples of the tree. Two of its trees are among the 30 largest giant sequoias in the world. The grove closed on July 6, 2015, for a restoration project and reopened on June 15, 2018.