Atlanta does have a beltway, it's I-285. When northbound south of Atlanta join I-285 West and follow until your just south of Marietta and then rejoin I-75. If you want to save some time and it's not rush hour, stay on I-75 into downtown and pick up I-20 West (the fire was north of I-20), follow west to I-285 and then to Marietta and rejoin I-75. Just take a look at the map, there are many options without going to Alabama.
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