Yes, you can enter the pool area even if you don't plan on swimming and aren't wearing a swimsuit. You still gotta pay, though those cards probably work
Would they accept swim for free cards from a library?
They are usually pretty cool about letting non-swimmers in, but keep in mind around busy times they have a cap on how many people are allowed inside, and Sideliners might be eating up a valuable swimmer's place, or they might just turn you away.
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