The beach opens at noon and closes at 7 pm. The main park opens before and closes after.
Glenn Borders' answer was correct. When we visited Lagoon on June 20 & 21 of 2022, Lagoon-A-Beach was open from 12:00pm to 7:00pm. Hours are posted on its website. If you go for more than 2 days, get a season pass. It will be cheaper than daily tickets.
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