The location you're asking questions about is for an activity complex not for the "chain of lakes" themselves. So to answer your question, in regards to this facility, no there are no old fashion defining holes or lakes to swim in.
Alot of people go to Eagle Lake by the boat ramp. There is a small beach area. Has tables. Be sure to use swimers ear after being in the lake for safety!
Lake Summit (very near Legoland) has a boat launch, a dock and a submerged "beach" (maybe 75yds long). The kids like to jump off the dock and swim around a bit, the beach is good for sitting up to your waist and letting the little fishes nibble at your feet and to boat launch / human activity keeps the gators at bay. As with any Florida open body of water, use caution and don't ingest or inhale the water.
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