I don't think this would be a great place to learn how to ride a bike. Part of the trails are paved so that section might work but I would suggest looking at Little Mulberry park instead.
Definitely not a place for beginners of riding. Alexander park would probably be better in Lawrenceville off Sugarloaf and Old Snellville.
Shouldn't have any issue riding a bike through. I saw cyclists using the trail so all good
The paved areas are smooth but there are some hilly areas but nothing too steep.
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