in 1963 the first visitors on modern snowmobiles entered Yellowstone. Not long after, snowmobiling became the dominant way to tour the park in winter.
Still, pressure to plow park roads persisted, and Yellowstone authorities knew that they could not accommodate both snowmobiles and automobiles. The matter culminated in a congressional hearing in Jackson, Wyoming, in 1967. By this time, park managers felt plowing would dramatically alter the look and feel of the park’s winter wilderness. They thought snowmobiles offered a way to accommodate visitors while preserving the winter time experience. By 1968, an OSV program was formalized. In 1971, park managers began grooming snowmobile routes to provide smoother, more comfortable touring, and also opened Old Faithful Snow Lodge so visitors could stay overnight at the famous geyser.
Throughout the 1970s, 80s, and early 90s, visitation by snowmobile grew consistently. This brought unanticipated problems such as air and noise pollution, conflicts with other users, and wildlife harassment. Meanwhile, in 1972, President Nixon signed Executive Order 11644 which described how off-road vehicles, including snowmobiles, should be managed. This Executive Order requires each agency to: establish policies and provide for procedures that will ensure that the use of off-road vehicles on public lands will be controlled and directed so as to protect the resources of those lands, to promote the safety of all users of those lands, and to minimize conflicts among the various uses of those lands.
Now, if Trump would REVOKE EO 11644....