Hiking boots = laced.
Five Things to Do in Hot Springs National Park
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Not so fun news: A visit to America's national parks could cost you twice as much in 2018. (Another bummer: National Park Service's senior passes jumped in cost from $10 to $80 in August of last year.)

Better news: This Martin Luther King Jr. Day, you can visit any national park that charges an entrance fee for free (some of the 400+ National Park Service sites are free year round). In addition to the fee-waiving on this upcoming holiday, there are three other free entrance days throughout the year: April 21st, the first day of National Park Week; September 22nd, National Public Lands Day; November 11th, Veterans Day.

WATCH: South's Best National Parks 

From Dry Tortugas National Park in Florida to Big Bend National Park in Texas, there's no shortage of epic landscapes to explore in our own stomping grounds. See our list of the South's National Parks here and start googling trail mix recipes. And while we have you, yes, now is the time to finally plot that long overdue plan to visit Denali National Park and Preserve in Alaska. Perhaps the week of April 21st?

For more information, visit NPS.gov.