The U.S. National Park Service preserves 390 parks, historic sites, memorials, and recreation areas that attract nearly 300 million visits every year. There are 58 national parks in the system, as varied as the country that houses them. Yellowstone thrills visitors with its explosive grandeur, The giant wonders of Sequoia, the frozen beauty of Wrangell-St. Elias--to experience them all would take a lifetime. A British diplomat once called national parks the best idea America ever had.