Yes, you have to pay for the swimming. But you can not have a chance to jump, or dive as the lake area open to swim is shallow. Mainly for novice visiters and family picnics.
Yes, you do have to pay. I think its only about $3-$4 though. If you go when there's no lifeguards, its free, but there's only one small area to swim. Its been a few years, but thats what i remember.
Lake Anza allows swimming but you should check with Tilden Park officials for exact details on seasons, the charges, etc.
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