Imagine going out for your morning jog and coming across an Enchanted Forest of Books. Or a UFO. Or a wooden man in what seems to be a giant steel bucket. It is a distinct possibility during the city’s largest temporary public-art exhibit, on view from September through November each year. Artwork from more than 70 artists is scattered over nine miles of the Atlanta BeltLine, an ongoing urban development project that—when all is said and done—will comprise a network of public parks, trails and transit by reusing 22 miles of mostly abandoned rail lines.