The U.S. National Park Service is celebrating its 103rd birthday, and is offering free entry fees at every park in honor on Sunday. It includes all 61 parks, including destinations like Yellowstone, Grand Canyon, and Yosemite. About two-fifths of the parks are free to enter all year-round, while the rest do charge entry fees. In all, the NPS oversees 419 places to visit, of which 112 charge a fee, according to CNN. However, they will all be free this Sunday, in honor of President Woodrow Wilson signing congressional legislation creating the National Park Service on August 25, 1903.