After reading some of the reviews mentioning long lines, I was apprehensive, but we got lucky, it was not at all crowded. We had so much fun! I had not originally anticipated staying the whole time, but since you don't waste energy walking up the hill (the magic carpet takes you up), we ended up playing at the tube runs basically from 10:00 to 4:00, when it closed.
What is great is that you get the all-day pass, and can come and go as you please. Parking is free. So, we were not stuck eating whatever snacks the place offered (fries, nachos, chicken nuggets) but actually had a nice lunch in town and came back afterwards for more fun. (Tip: get the tag put on some item of clothes you are sure not to want to take off! My daughter had hers originally on her ski bib, which ended up being much too warm. We got a new tag without any trouble, showing her pants, but it did interrupt the day for a bit.)
Another note: I actually ended up here by mistake - I had intended to go to a place called Snow Play, and thought this was it. Only noticed after a while, that these tube runs had no bumps. So, if you're after the bumps, you need to keep driving a bit further. What this place had though, was the additional fun of the Alpine Slide, and albeit pretty expensive, it was very different and quite a treat.
Overall, a very fun day - will definitely go again. Some people complain about the lack of supervision and security - personally I enjoyed the fact that nobody tells you how to go down the hill. Face first, on your knees, daisy-chained together with your friends - it's all good.
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