The new Yosemite Valley Visitor Center is built. Fire destroys Mountain House and Glacier Point Hotel. 1970 Free shuttle bus begins in Yosemite Valley. To stimulate new tree growth and to decrease danger from fire hazard, prescribed burning of selected forest undergrowth begins. Yosemite Institute, an environmental education organization is founded.
Mirror Lake is dredged for the last time.
1972 Wilderness permits are required for backcountry hikers and campers. 1974 Hang gliders are allowed to take off from Glacier Point. 170 flights are recorded. Trailhead quota system launched to control backcountry use. The Yosemite General Management Plan, the parks's first, long-range plan addressing issues of overuse and how best to preserve Yosemite's environment, is completed and approved.