There are options. It is $15 for 45 mins but you can buy passes for 3 45 min sessions for $25 or an all day pass for $50. There is a discount if you are camping in the park. There is also a Groupon right now so look into that before you go.
You can call them and ask for the Groupon discount. You don't actually need to buy a groupon. They also have Facebook coupons all the time.
$15 for 45 mins
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