Big Sioux Recreation Area was established in 1978
6am to 10pm until October 1, then 8am to 8pm until April 1. I could be a little off from the timing, but should get you close
I don't know for sure when the park was established, but I am 61 years old and a friend of the same age remembers when they were tearing down the A-frame house that surrounded the current Log Cabin that sits in the park. Best guess would be 30 plus years ago.
Open at 8 Am and closed by 9 PM and it remains open year-round
Big Sioux Rec is open year-round
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