My dad works there and I am in a wheelchair and I can get around pretty well. About half if not more are paved I'm sure you already got the answer.
You can do close to an hour of biking on paved trails by going to the nature center and back and doing the large circle and repeating as needed. A couple of road crossings. Water sometimes covers the trail at the bottom of one hill to the nature center. Deer can be an attraction/hazard.
The multi use trails are paved throughout the park. There are bridle paths and nature paths like the board walk where bicycles are prohibited. The biking trails are on Google maps.
The Young Lady and I took roller blades and really enjoyed it... nice and smooth. I think everything on the one side is paved except the swamp boardwalk. On the side with the Observation Tower, there are mostly gravel trails, so park on the north end for the paved trails. Perfect for biking though.
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