Assuming stone mountain is a theme park, this is what it says on their FAQ:


* Do you have bike trails or somewhere for me to ride my bicycle at the Park?
Bicycles can be ridden along the roadways inside the Park. There is a dedicated bicycle lane on Robert E. Lee Blvd., on the back side of the mountain. Bikers must ride single file and follow all traffic laws.


If it's a theme park, I'm assuming it's private land & roads.