On June 30, 1864, Abraham Lincoln signed the Yosemite Grant Act, which ceded Yosemite Valley and the Mariposa Grove of Giant Sequoias to the state of California. This act stipulated that the land be held "for public use, resort, and recreation" and be inalienable. It is considered a landmark event in the history of conservation and is seen by many as the beginning of the national park concept.