Sandals or personally Walmart flip flops are good for this type of thing.
One thing i can recommend is wearing sandels cause I dont belive they aren't allowed. The only hastle would be finding a place to put them when you want to swim or go on a slide cause nobody wants to pay $2 for a locker that last an hour when you will constantly be walking. Unless you hide them but i tride that once and they where taken. Unless and i know this sounds stupid but, wet socks. Any time you need to swim you can put them in your pocket (assuming your swim trunks have pockets). But they also have the downside of warming up when walking and eventually getting really hot.
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