You can visit the country's national parks and forests for free on Martin Luther King Jr. Day, the first fee-free day of the new year.
If you want to double down on free, there are plenty of free things to do when you arrive at a park near or far. Each of the five parks below have downloadable online guides and newsletters on their websites that detail activities, hiking trails and sights to see.
Here are some free activities to get you started:
Sequoia & Kings Canyon (Central California): Learn about the signature trees at this park, the giant sequoias, on a Grant Tree Walk at 10 a.m. Monday. You'll see the massive General Grant and other behemoths in Grant Grove. Hike takes about an hour and a half; meet at the Grant Tree parking lot. Info: Sequoia-Kings Canyon National Parks
Yosemite (Northern California): Start Monday with a 9 a.m. hour-long Camera Walk to take photos of the park in winter. It starts at the Ahwahnee Hotel, but visitors must sign up in advance at the Ansel Adams Gallery in Yosemite Village. Or join a free snowshoe tour at 10:30 a.m. (conditions permitting) at the Badger Pass Ski Area. Snowshoes are provided. Info: Yosemite National Park
Grand Canyon (northern Arizona): Take a 10 a.m. hour-long tour of Kolb Studio on Monday. It's the home and photography studio of the brothers who started snapping pictures of the park at the turn of the last century. Then join a 1:30 p.m. ranger-led rim walk to learn about the history and ecology of the massive canyon (meet at Verkamp's Visitor Center). Info: Grand Canyon National Park