Beginning at its southern terminus with Interstate 75, Interstate 675 is a four lane highway with a grassy median and frequently with cable barriers. Between Ellenwood Road/Forest Parkway and the route's northern terminus at Interstate 285 and Moreland Avenue, the freeway expands with three lanes in each direction.
As of 2010, the idea of connecting I-675 and SR 400 has been resurrected, being put on an official list of GDOT priorities. This would extend I-675 north to I-20 with a surface road, then go underground with a road tunnel. This would displace some neighborhoods and industrial areas to the south. The tunnel would protect other areas north of I-20, however there would still be ventilation buildings.