Thank you😊
It is not free. They charge national park rates, however, if you are a senior and purchased/have a lifetime senior pass ($80), entrance is free and camping rates are 1/2 price. There are also discounts for military. I believe the longest you can stay at any national park is two weeks, but check online or call for specifics. This website should prove helpful. https://www.recreation.gov/pass/atb. Happy camping!!
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