Saturday is going to be a big day for nature lovers.
It’s America’s 30th annual National Public Lands Day.
Not only will hundreds of federal lands offer visitors free entry, but it’ll also be the biggest day of the year for volunteering at parks and public lands, according to the National Environmental Education Foundation, which coordinates National Public Lands Day in partnership with federal agencies, nonprofits, and state and local parks.
Over 70,000 volunteers are expected to chip in on hundreds of service projects across the country, ranging from pulling weeds along the Atlanta BeltLine to painting fences at Bryce National Park to taking photos of fall colors at Round Lake Logging Dam in Wisconsin.
Of course, you don’t have to donate your time to enjoy these places for free on Sept. 23. Here’s what travelers should know:
Which national parks are free to visit?
All 425 sites within the National Park System will offer free entry on National Public Lands Day. That includes every national park as well as national battlefields, monuments, seashores and more.
Not every site charges entry fees regularly. Additionally, some parks have museums, parking and other facilities operated by third parties that may still charge fees, according to the National Park Service.
When else are national parks free?
Aside from National Public Lands Day, there will be just one more free-entry day this year, Veterans Day on Nov. 11.
All year-round, national parks also offer free entry to:
◾ U.S. citizens and permanent residents with permanent disabilities.
National parks for every body: How to make the outdoors more accessible to people with disabilities
How do I volunteer?
The National Environmental Education Foundation has set up a searchable database of National Public Lands Day service projects around the country.
Events can be searched by location and keyword.
This article originally appeared on USA TODAY: Free: National parks waive entry fees, welcome volunteers on Sept. 23