Georgia State Route 400
State Route 400 is a freeway and state highway in the U.S. state of Georgia serving parts of Metro Atlanta. It is concurrent with U.S. Route 19 from exit 4 until its northern terminus south-southeast of Dahlonega, linking the city of Atlanta to its north-central suburbs and exurbs. SR 400 travels from the Lindbergh neighborhood in the Buckhead district of Atlanta, at I-85, to just south-southeast of Dahlonega. Like the Interstate Highways, it is a limited-access road, but unlike the Interstates, the exit numbers are not mileage-based, they are sequential. Once SR 400 passes exit 18, it changes from a limited-access freeway into an at-grade divided highway with traffic lights, but still with a speed limit of, and ends at the J. B. Jones Intersection at SR 60/SR 115 in Lumpkin County.
Between I-85 and I-285, SR 400 is designated "T. Harvey Mathis Parkway", after a local land developer and road proponent who died the day after being appointed as head of the Atlanta Committee for the Olympic Games in June 1991, when the tollway was under construction. Upon reaching the Perimeter and beyond, the highway is designated "Turner McDonald Parkway", after a Fulton County Public Works Department director.
SR 400 is one of only two state routes in the 400–499 series to not be designated as an unsigned route following an Interstate; the other is SR 410 near Stone Mountain. Both SR 400 and SR 410 were originally planned as interstate routes: SR 400 was supposed to be I-485 and SR 410 was supposed to be I-675.
Route description
SR 400 begins at I-85 just north of Downtown Atlanta. SR 400 travels concurrently with MARTA's Red Line between its Buckhead and Medical Center stops; the Red Line's final stop is at the North Springs station. SR 400 southbound can access the station via Exit 5C, and traffic from the station can enter SR 400 northbound.SR 400 goes through a tunnel under the Atlanta Financial Center in Buckhead, south of SR 400's exit 2. Farther north, SR 400 meets I-285, also known as "The Perimeter" or "Atlanta Bypass".
At I-285, SR 400 meets with US 19. The two travel concurrently until an intersection with SR 60 and SR 115 in Dahlonega.
North of I-285, SR 400 travels through Sandy Springs, Roswell, and Alpharetta in Fulton County. Major junctions include SR 140 and SR 120.
From US 19 and I-285 in Sandy Springs, SR 9 travels parallel to SR 400 to the west until SR 9 reaches Coal Mountain. In Coal Mountain, SR 9 veers northwest away from SR 400, but then later turns northeast toward its northern terminus at its intersection at US 19 in downtown Dahlonega.
SR 400's exit 6 at Northridge Road is known as the Mayor Eva Cohn Galambos Memorial Interchange.
From SR 400's exit 8, Mansell Road, to exit 11, Windward Parkway, North Point Parkway travels parallel to the east of SR 400. North Point Parkway provides access to North Point Mall.
SR 400 enters Forsyth County at the overpass of McGinnis Ferry Road. In the county, SR 400 travels through Cumming and Coal Mountain. Major interchanges include SR 141, SR 20, SR 306, and SR 369. SR 400's limited-access portion ends at SR 369, and SR 400 continues on.
Travelers can access Bald Ridge Marina and boat ramps for Lake Lanier via exits 15 and 16.
North of SR 400's intersection with Jot Em Down Road, SR 400 continues into Dawson County, where it travels through Dawsonville. Major intersections include SR 53 and SR 136.
At the intersection of SR 400 and SR 53, a continuous-flow intersection was completed in May 2017. Near this intersection is the entrance to North Georgia Premium Outlets.
SR 400 continues into Lumpkin County just south of its intersection with Whelchel Road and Wilson Drive. After traveling in the county, SR 400 and US 19 meet SR 115 from the north and SR 60 from the east. SR 400 ends at this point, and US 19 turns left and continues north through downtown Dahlonega into the Appalachian Mountains and the Chattahoochee–Oconee National Forest.
All of SR 400 south of the Dawson–Lumpkin county line is included as part of the National Highway System, a system of roadways important to the nation's economy, defense, and mobility.
Exits on the controlled-access part of SR 400 are numbered according to the consecutive numbering system instead of reference post numbering. This is unlike the Interstate Highways in Georgia, which have used reference post numbering since 2000, with the exception of I-24, which continues the exit numbering from Tennessee as the Interstate Highway crosses through Georgia back into Tennessee. This means that exit numbers on SR 400 start at 1 and use consecutive numbers regardless of the nearest mile marker.
At the southern terminus, new ramps connecting SR 400 south to I-85 north and I-85 south to SR 400 north opened on April 2, 2014. The project was two years in the making and was paid for with funds from the SR 400 toll plaza. Prior, drivers had to exit off SR 400 onto Sidney Marcus Boulevard to get to I-85 north. On I-85 south, drivers had to take the Cheshire Bride Road/Lenox Road exit to get to Sidney Marcus Boulevard for access onto SR 400 north. The ramp from I-85 south is shared with the SR 13 ramp. From SR 400, Sidney Marcus Boulevard is now exit 1B and the ramp to I-85 north is 1A.
In Forsyth County in 2017–2018, SR 400 was expanded from two lanes in each direction to three from McFarland Parkway to SR 369.
History
Planning for the freeway, later known as the North Fulton Expressway and the Appalachian Developmental Highway, began in 1954. The initial section north of I-285 was officially dedicated on May 24, 1971 and subsequent additions to the north opened in stages through 1981.Initial development was led by Fulton County Public Works Department director Turner McDonald, who worked for the county from 1947 until retiring in 1980. In January 1974, the Georgia General Assembly named a stretch of the highway—from I-285 to the Fulton-Forsyth county line—after McDonald. At the end of that year, on December 23, McDonald attended a ceremony officially dedicating the segment between Union Hill Road and SR 20 as Turner McDonald Parkway.
The road was widened in the late 1980s from its original four-lane configuration to eight lanes between I-285 and Holcomb Bridge Road, and to six lanes between Holcomb Bridge Road and Haynes Bridge Road. The widening projects were brought on by the massive growth that the freeway brought to northern Fulton and southern Forsyth counties. In 2005 the Georgia Department of Transportation began widening the section from Holcomb Bridge Road to McFarland Parkway from six to eight lanes. In addition, metal noise barrier walls and a concrete divider in the median were also added. In 2010, a half-diamond interchange was added on the north side of Hammond Drive, allowing southbound exits and northbound entrances.
The northern portion of the inside-the-Perimeter route remained alive following the freeway revolts, and after lawsuits by residents that spent several years in court, GDOT was able to force the extension through Buckhead. Dozens of homes were taken through eminent domain or the threat of it, and the highway was built through the middle of formerly-secluded and forested neighborhoods. Some remaining residents live on dead end streets with metal barrier walls. During planning stages of the highway in 1984, the Robinson-Humphrey Bank Company proposed a massive expansion of its office building in Buckhead, now known as the Atlanta Financial Center, which was to be built directly in the proposed routing of the highway. A compromise was worked out for Fulton County to pay $3 million to Robinson-Humphrey to offset extra construction costs. This allowed the new tower to be constructed with special concrete supports allowing for the highway and eventual MARTA Red Line to run underneath; the deal also covered Robinson-Humphrey's $1 million donation of the right-of-way to the Georgia DOT. Construction of the massive tunnel underneath the office complex and its parking garage was underway in 1990; the tunnel was sealed off with concrete to protect the building from noise and vibration. The original plans for the North Tollway put interchanges at Marion Road, Peachtree Road at North Stratford Road, Wieuca Road, Windsor Parkway, and Johnston Ferry Road. By 1972, plans had been adjusted to exclude the Wieuca Road exit and add an expressway connecting Andrews Road at Roswell Road to Peachtree Road at Lenox Road as an alternative to a direct interchange with Peachtree Road. The mainline toll booth would have been south of Peachtree Road. By 1986, the present alignment with only 3 exits and a single tollbooth north of Peachtree Road were finalized, eliminating direct access to both Peachtree Road and the residential Buckhead neighborhoods. Atlanta City Council member Buddy Fowlkes was opposed to the extension of GA 400; "I'm encouraged," he said in 1989. "People are starting to understand that there are alternatives to the Georgia 400 extension." In 1991, the State Road and Tollway Authority authorized $96 million in bonds to pay for the GA 400 Buckhead extension which would be paid back by 2011 with toll revenue.
The road opened to traffic on August 1, 1993, after three years of construction. Existing exits were renumbered up by four to accommodate the extension, which had a single toll plaza in the middle of its length when opened.
In addition, the North Line for Atlanta's MARTA train system was constructed in the median from the Glenridge Connector to south of Lenox Road, and was opened on June 8, 1996, extending the line from Lenox Square mall north to Perimeter Mall, and connecting the Perimeter Center area to the rail system. That edge city largely developed due to its proximity to the 400/285 interchange.
Direct access from SR 400 southbound to I-85 northbound opened in April 2014, ending the need to take the indirect route via Sidney Marcus Boulevard. In June 2015, a ceremony was held to name the flyover bridges for Captain Herb Emory, a beloved local traffic reporter for WSB AM and WSB-TV who had died in April 2014. At one time, SR 400 was to connect to I-675 in southeast DeKalb county. However, residents in intown Atlanta neighborhoods did not want the highway to cut through and partially destroy their neighborhoods, and a freeway revolt ensued, ending when then-Governor Jimmy Carter signed a new city charter and the USDOT rejected the highway studies in 1973, and George Busbee had the plan officially terminated when he became governor in 1975. The point where this road would have had its interchange with the also-doomed I-485 is now the site of the Jimmy Carter Library and Museum. A later routing of I-485 would have had that number running from the Downtown Connector east to the current library, then north on what is now SR 400. A revival of the connection to I-675 was proposed in 2009. A tunnel would go under East Atlanta and other neighborhoods in Atlanta on the DeKalb-county side, south to I-20. A surface road through less-developed land would then go south to I-675. The project would be a public/private initiative. As of September 2024, the project is not on the GDOT's Major Mobility Investment Program List
Funding for a project to create a new interchange on SR 400 at SR 369/Browns Bridge Rd came from the Forsyth County Transportation Bond, approved by voters in 2014, along with GDOT funding. Previously, SR 400 met SR 369 at a signalized intersection, where the freeway part of SR 400 ended. Plans showed that a partial cloverleaf interchange would be built, with ramps from both directions of SR 400 meeting SR 369 at traffic lights; the northbound SR 400 ramp would also meet at the entrance of Browns Bridge Church. Also as a part of this project, SR 369 will be widened from its intersection with SR 9, through the interchange at SR 400, to its intersection at SR 306. The widening project is currently still underway as of 2023. Workers cleared the area and removed underground storage tanks, per county officials. Forsyth County acquired four properties as part of right-of-way acquisition and is expected to go out for bid in the fall of 2019; a bid is expected to be awarded in early 2020. Construction began in late 2020 and the interchange opened in early 2023.