(CNN) -- It was during the throes of the Civil War, with lots of bloody and brutal fighting still ahead, when President Abraham Lincoln turned his attention to the Mariposa Grove and the Yosemite Valley areas of California.
Lincoln's signature on the Yosemite Land Grant bill on June 30, 1864, set a precedent for the preservation of the young country's wilderness. That act 150 years ago was the first instance of the U.S. government setting aside scenic wilderness for public use and preservation.
The act put both tracts of land in trust for the state of California, and it set the stage for the 1872 establishment of Yellowstone National Park in Wyoming, Montana and Idaho as the first national park.
The land around the grove and the valley became Yosemite National Park in 1890. Both pieces of land were re-acquired by the federal government and combined with the national park in 1906, which created the park much as we know it today.
Yosemite now hosts 3.7 million visitors annually, and the numbers are expected to swell for anniversary events through October. But the glorious groves of ancient sequoias, spectacular waterfalls and 750 miles of trails that are now Yosemite National Park's 1,200 square miles are a joy for travelers to visit any time of year.