The National Park Service is 98 years old Monday and it's celebrating by letting the public into all its parks and monuments for free. That includes 22 in Arizona.
Some are well known, like the Grand Canyon in the north or Saguaro National Park in the south. Closer to the Valley, there’s Casa Grande Ruins. And a few days a year, they all become free.
Sherry Henry is the director of the Arizona Department of Tourism. She said these freebies are a way to entice all kinds of people to visit the parks, especially those who live in the state.
"There are people coming from all over the world to see these parks," Henry said. "And so we want to remind Arizona residents that those treasures are a very short drive away."
Henry said she's not sure how much these free entrances increase visitation, but Arizona national parks draw more than 10 million visitors each year. The park service has two more free days left this year. National Public Lands Day is Sept. 27 and Veterans Day is Nov. 11.