Yes! I believe they have Mirror Lake and Devil's Lake. You can also check by searching on google for Wisconsin Dells lakes for swimming and you will find something. But be careful because some of those lakes you have to pay. I believe Devil's Lake has a fee. Not sure what is the fee though.
Almost every place has at least a swimming pool. Noah's Ark, Wilderness Resort both have indoor Waterparks & Mt. Olympus is outdoor Waterpark. Not to mention the lakes & River itself. Lighthouse Condos for example has an indoor & outdoor pool, plus several small beaches on Lake Delton.
We stayed at the Wilderness resort and they had 6 outdoor water parks and 3 indoor waterparks. Highly recommended to anyone with children. Lots to do and an awesome time!!
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