Looking for something to celebrate? The National Park Service is turning 100. In honor of that milestone, the organization is waiving admission fees to National Parks across the country this weekend. From Thursday, August 25 to Sunday, August 28, families will be able to connect with nature at Yellowstone National Park, Yosemite National Park, Glacier National Park, and more than 100 others without reaching for their wallets.

President Ulysses S. Grant established Yellowstone as the first National Park in 1872; 44 years later, President Woodrow Wilson signed the National Park Service into existence. Today, the National Park Service maintains 412 designated NPS areas that span more than 84 million acres across the country. Before you plan your trip, consult the NPS website, which lists, by state, all of the parks, areas, and preserves that will be participating in the free entrance days.

If you can't fit in a visit this weekend, there will more opportunities to pay homage to the NPS and the beautiful land it protects. Other centennial events taking place this year include new postage stamps and a National Parks Adventure IMAX film.