The first of 2017's free-admission days at U.S. national parks is already behind us—it was Martin Luther King Day.
But before the year is over you'll have nine more chances to enjoy at no charge all the sites maintained by the National Park Service—from all-time faves like Yosemite and Yellowstone to overlooked gems such as Big Bend in Texas and Crater Lake in Oregon.
Here are the remaining dates when you can experience all that natural splendor for free:
February 20, Presidents' Day
April 15-16 and 22-23, the weekends of National Park Week
August 25, the National Park Service's 101st birthday
September 30, National Public Lands Day
November 11-12, Veterans Day weekend
Finally, these visitors will get in for free every day the parks are open: active-duty military service members, citizens with permanent disabilities, and kids in fourth grade who sign up for the Every Kid in a Park program (their families aren't charged admission, either).