Children age 5 - 12 require a child ticket to enter. Adult rate tickets are for ages 13+. Yes, get a hand stamp at the gate for same-day re-entry.
Come with your own adult tickets, I don't think nine-year-old will get in for free, but your 3 and 4 year old can get in for free. As long as you have your hand stamped you can go back and forth to your car as many times as you need to
Many discount for siniors
Kids were free last weekend. They are not free now, but child tickets are available. You can get a hand stamp, at the exit, for readmittance the same day. So you, you can go to your car and come back in.
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