Mike's has the best selection and a huge display both inside and out so if you're looking for something big or obscure, you'll probably find it here and only here. If nothing else, it was fun to look at everything and a great place to pass the time waiting for cave tours to start because its close to several of them.
If you're looking for rocks, this is the place to go. However, if you're looking for cheaper rocks of the sort most everyone in the area is selling, you'll find them in the main stretch in the little gift shops. I can't remember the name of it, but there's one with a bunch of statuary out front that we found rocks for near half the price.
The rock shop is in the lower half of the parking lot and a general gift shop in the upper, along with the mystery house - which looks rather like a mystery shed at first glance. Print out the free family pass online. I don't know as I'd pay for this short adventure but the room where everything is on a slant is hilarious and would almost be worth the dollar admission.
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