Yosemite National Park may be one of the world's most impressive landscapes, with its granite cliffs, towering waterfalls, and ancient sequoia groves. But while the beauty of the valley and surrounding mountains is a product of 10 million years of geologic shifts and slow evolution, the park itself is a legal creation, and a very important one at that. Yosemite became the nation's first parkland set aside for preservation when Congress passed the Yosemite Grant Act, signed into law by Abraham Lincoln on June 30, 1864. That act planted the seed that would grow into the National Parks System, or, as the writer Wallace Stegner described them, "America's best idea."
Now, Yosemite is growing larger still, with the addition of 400 acres of meadowland and ponderosa pine, the park's largest expansion in two generations.