The incredible beauty of Yosemite began about 130 million years ago when a 400-mile fault line, along what is now the eastern edge of the Sierras, broke lose, and the ground on the western side was forced up to heights of over 10,000 feet. During the Ice Age, Yosemite Valley lay under 6,000 feet of ice, the Tuolumne Meadows Visitors Center under 2,000 feet. Over the millions of years since, the ice and erosion sculpted the Yosemite area into the spectacular scenery you see today.

Some 4,000 years ago, Native Americans moved into the Sierras from the east, probably looking for game and water in dry years. Later, Miwok-speaking people moved into the same area from California's central valley. Gradually the two groups merged, and for centuries they were a peaceful people living a "hunter-gatherer" life in the greater Yosemite area, including the Mono Lake region, where the group came to be known as the Paiutes. They spent summers in Yosemite Valley, which they called "Ahwahnee" and moved to the lowlands when winter came.

European-Americans came to the area in the 1850s looking for gold. They forced the Miwoks out of the central valley and into the mountains, despite the harsh climate. As the search for gold continued, clashes between the Native Americans and European Americans increased, with the European Americans rounding up bands of Indians and forcing them into the Mono Lake and other areas beyond the mountains. By the 1870s, there were fewer than 50 Miwoks in Yosemite Valley and the area around it. Today, visitors can hear this story at the Indian Village of Ahwahnee.

Word of the wonders of Yosemite spread quickly. In 1855, James Mason Hutchings brought the first group of tourists to the valley from San Francisco. Artist Thomas Ayres was one of the visitors and his sketches spread the fame of the area even more rapidly. Hutchings continued to promote the area, and soon roads and crude hotels were built, allowing for more and more visitors.

Early conservationists, I.W. Raymond and Fredrick Law Olmstead (the landscape artist who later created New York's Central Park) visited Yosemite and believed it should be preserved. They worked with Congress to protect the area. On June 30, 1864, President Abraham Lincoln signed a bill that granted Yosemite Valley and the Mariposa Grove of Big Trees to the State of California, effectively creating the world's first national park and limiting development in those two, small areas.

Rampant growth, however, continued outside the protected areas. Many, including Hutchings, scrambled to create hotels and other services to profit from the growing number of tourists. Logging, mining and stock grazing boomed as well, threatening to degrade the area.

John Muir first visited the park in 1868, returning the next summer to work as a sheepherder in the high country. In 1869, he moved into Yosemite Valley, doing odd jobs and building a cabin on Yosemite Creek. In 1871, he wrote the first of a series of newspaper articles that spawned much of the public sentiment in favor of protecting the region. He joined forces with Robert Underwood Johnson, editor of the influential Century Magazine, and the two of them resolved to create a much larger Yosemite National Park.

On October 1, 1890, the U.S. Government enacted the law, which created a park that was about 25 percent larger than the current one. Surprisingly, it did not include either Yosemite Valley or the Mariposa Grove of Big Trees, which were still run by the State of California. The U.S. Army was put in charge of the National Park, and their work lives on today. They blazed trails, explored unknown areas, chased poachers and prepared many maps.

Of course, this dual control led to political differences. Soon John Muir, the newly formed Sierra Club and various citizens began to push for unification. In 1896, California formally deeded Yosemite Valley and the Mariposa Grove to the Federal Government. The army continued to run the park, headquartering in the Valley.

The first automobile arrived illegally in the Valley in 1900, and by 1907 the Yosemite Rail Road was completed between El Portal and Merced, making it even easier for tourists to visit. In 1913, the army legalized cars, and they came in droves.

It was during this period that public campgrounds, including Camp Curry and other concessions, were built. In 1913, San Francisco was granted the right to dam the Tuolumne River at Hetch Hetchy over years of protesting by John Muir, the Sierra Club and other environmentalists. Many consider this the nadir of the management of the park.

The creation of a National Park Service to replace the army in 1916 signaled a change in thinking on park management. The new agency was charged to "conserve the scenery and the natural and historic objects and wildlife therein, and to provide for the enjoyment of the same in such manner and by such means as will leave the unimpaired for the enjoyment of future generations." This phrase still guides the National Park Service; it led to the creation of the many interpretation programs that are currently available to the public.

Today, science informs many of the efforts to preserve the park. Fire is regarded as a management tool, wild life is studied and protected, and artificial events like the Fire Fall from Glacier Point have been stopped.

The biggest challenge for the Park Service now, is how to keep the park accessible to the more than four million annual visitors without destroying it. To that end, park maintenance issues are constantly negotiated, such as the limitations on cars; they grow more stringent every year.