Yellowstone is a geological smoking gun that illustrates how violent the Earth can be. One event overshadows all others: Some 640,000 years ago, an area many miles square at what is now the center of the park suddenly exploded. In minutes the landscape was devastated. Fast-moving ash flows covered thousands of square miles. At the center only a smoldering caldera remained, a collapsed crater 45 by 30 miles. At least two other cataclysmic events preceded this one. Boiling hot springs, fumaroles, mud spots, and geysers serve as reminders that another could occur.
Yellowstone, however, is much more than hot ground and gushing steam. Located astride the Continental Divide, most of the park occupies a high plateau surrounded by mountains and drained by several rivers. Park boundaries enclose craggy peaks, alpine lakes, deep canyons, and vast forests. In 1872, Yellowstone became the world's first national park, the result of great foresight on the part of many people about our eventual need for the solace and beauty of wild places.
In early years, what made Yellowstone stand out was the extravaganza of geysers and hot springs. The wild landscape and the bison, elk, and bears were nice but, after all, America was still a pioneer country filled with scenic beauty and animals. [Visit Yellowstone National Park in Winter with National Geographic Expeditions.]
As the West was settled, however, Yellowstone's importance as a wildlife sanctuary grew. The list of park animals is a compendium of Rocky Mountain fauna: elk, bison, mule deer, bighorn sheep, grizzly bears, black bears, wolves, moose, pronghorn, coyotes, mountain lions, beaver, trumpeter swans, eagles, ospreys, white pelicans, and more.
During the summer of 1988, fire touched many sections of the park, in some areas dramatically changing the appearance of the landscape. Yet not one major feature was destroyed. The geysers, waterfalls, and herds of wildlife are still here. Many places show no impact at all, while those that are regenerating benefit both vegetation and animal life. Side by side, burned areas and nonburned areas provide an intriguing study in the causes and effects of fire in wild places. Yellowstone has witnessed bigger natural events than this and may well again.
Of far greater concern to environmentalists than the fires are the impact of the increasing numbers of visitors, the threatened grizzly bear population, and, on nearby lands, the planned development of natural resource projects. Cooperative management between the park and the six forests that make up the greater Yellowstone ecosystem is essential if wildlife and thermal features are to survive.
Most of the park rests atop a slumbering volcano that erupted half a million years ago and is showing signs of renewed activity. (Note: No eruption is expected in the near future.)
There are more geysers and hot springs here than anywhere else on Earth.