Six Flags over Georgia/Six Flags Water Park. Piedmont Park. Look for some events going on during your stay. Atlanta Zoo Silver Comet Trail Lake Allatoona/Red Top Mountain trails Marietta Square (Kennesae Mountain first than go into the Square for food) Sandy Springs City Outdoor Concert Series Tour the Georgia Tech Campus
https://www.reddit.com/r/Georgia/comments/13hj82x/any_fun_outdoor_activities_near_atlanta/