English: Logo of the United States National Park Service, an agency of the United States Department of the Interior. This version is shaded to look as if it has been carved out of wood or rock. The elements on the logo represent the major facets of the national park system. The Sequoia tree and bison represent vegetation and wildlife, the mountains and water represent scenic and recreational values, and the arrowhead represents historical and archeological values. The bison is also the symbol of the Department of the Interior. The logo became the official logo on July 20, 1951, replacing the previous emblem of a Sequoia cone, and has been used ever since. The design was slightly updated in 2001, and a few different renderings are used today. For more information, see here and here.^{[dead link]}