I will be in Atlanta in the beguning of August , I would like to spent the weekend in a near city/ town ( 3-4 hours drive ) , something with nature , maybe a beach near by , any suggestions ? Nathalie

There's Savannah with nearby beaches (3.75 hours) or Asheville, NC (3 hours). Given that it's August, unless you really want to see the ocean, I'd choose Asheville (should be more comfortable weather-wise).

Chattanooga is about 2 hours away. Good aquarium, and some nice parks and hiking trails.

Idea.

One day/overnight in Savannah,
One day at Jekyll Island, Tybee or Cumerbland Island (about 1.25 hour drive from Savannah)

All have different offerings.
Jekyll and Cumberland have most nature.

The coast is a bit of a drive, but Savannah/ Tybee are very nice.

About an hour away is an antebellum town that was not burned when Sherman came through. If you want to see an old Southern town, Madison is gorgeous and relaxing, but not a lot to do.

If you like nature and want different water, you could head into the mountains of North Georgia. Take a whitewater rafting trip on the Chattaga River (where Deliverance was filmed) or rent a boat on a mountain lake, take hikes to waterfalls, etc. It would be a very cool (as in temperature) option in August.

You can drive 2 hours north to the Murphy, NC area (Smoky Mtns), which is just over the border from Blairsville, close to whitewater rafting, waterfalls, GSM Nat'l Park and Railroad, and more! Let me know if interested and needing accommodations, I may be able to help you out.