by side through the interchange, which actually has two parts. The interchange also features many other, not as important local access roads at the same time; meanwhile providing access to Hartsfield–Jackson Atlanta International Airport. I-85 then runs along the northwestern boundary of the airport in East Point, providing access to the domestic terminal. At the southwestern edge of Atlanta's city limits, I-85 merges with I-75 to form the Downtown Connector, which is 12 to 14 lanes wide. At the southern edge of Downtown Atlanta, this freeway has an interchange with the major east–west Interstate Highway, I-20. The two freeways then skirt the eastern edge of downtown, running due north, passing through the Georgia Tech campus and the Atlantic Station section of Atlanta before the two highways split, with I-75 exits via the right three lanes and then heads northwest while I-85 uses the left three lanes and then heads northeast. Atlanta to South Carolina state line Heading northbound after the Brookwood Interchange with I-75, I-85 is routed along a 10-lane-wide viaduct from the Buford Highway Connector (exit 86) to SR 400 (exit 87). Continuing northeast of Atlanta, I-85 continues through the northeastern suburbs, bypassing Chamblee and Doraville, where there is another intersection with I-285 (nicknamed Spaghetti Junction). The Interstate then travels through the northeastern suburbs of Atlanta, including Lilburn, Duluth, Lawrenceville, and Buford. The Interstate has freeway interchanges with SR 316 in Duluth and I-985 in Suwanee, which provides a link to Gainesville. I-85 eventually leaves the Atlanta metropolitan area and narrows down to four lanes (two in each direction) past exit 129 as the highway continues into the rural parts of northeast Georgia. At Lake Hartwell, which was formed by the damming of the Savannah River, I-85 crosses the Savannah River into South Carolina. Express lanes I-85 has the first express lanes in Georgia, located in Gwinnett and DeKalb counties; they were originally high-occupancy vehicle lanes (HOV lanes). From Chamblee–Tucker Road (exit 94) to Old Peachtree Road (exit 109), travelers that utilize the converted lanes will be charged a toll varying from , depending on traffic conditions and usage. Though not signed on the freeway, they are high-occupancy toll lanes (HOT lanes), which means registered transport vehicles, carpools with three or more occupants, motorcycles, and busses are exempt from toll charges as long as they are registered as such. Tolls are collected using an electronic toll collection system. All