In late August 1916, Woodrow Wilson brought the National Park Service into existence. At the time there were 35 national parks. Today there are 394, located in 49 states (Delaware is the odd state out), the District of Columbia, American Samoa, Guam, Puerto Rico, Saipan, and the Virgin Islands. The NPS employs more than 20,000 workers who care for 84 million acres of parks.
Here's a look at some national park superlatives, from the biggest park to the most visited.