SR 4 begins at the Florida state line, at a bridge over the St. Marys River, south of Folkston.

Between an intersection with the northern end of Amanda Street and one with Morton Avenue, they cross over the city's drainage canal.

Almost immediately, they intersect Fulford Road, which leads to the Ware County Sheriff's Office, the Southland Waste Transfer Station, the Ware County Emergency Management Agency, and the Waycross Regional Youth Detention Center.

Almost immediately, they cross over the Satilla River on the Charles Ray King Memorial Bridge and curve north.

US 1, US 23, and SR 4 cross over Little Hurricane Creek on the PFC Clarence Loran Gaskins Memorial Bridge and then curve to the northwest.

Upon entering Alma, they pass Bacon County High School Just south of an intersection with Floyd Street and Radio Station Road, they begin a curve to the northeast.

Between 8th and 6th streets, the highways begin a curve to the northwest and pass the Alma Bacon County Welcome Center.

They cross over Bear Branch and then meet the western end of Magnolia Drive, which leads to the Alma Bacon County Recreation Department.

They leave the city limits of Alma and cross over Hurricane Creek on the Curtis Lee Marion Bridge.

US 1 and SR 4 continue to the northeast and cross over Big Satilla Creek and enter Appling County.

They pass a picnic area just before crossing over the Altamaha River on the Joseph Simmons Alexander Sr. Memorial Bridge to enter Toombs County.

An intersection with South Washington Street leads to Partin Park and the Lyons Recreation Department.

They cross over Pendleton Creek and travel through rural areas with agricultural land on both sides of the roadway before entering Emanuel County.

They curve to the northwest, very briefly reentering the city, and then travel just to the west of Emanuel County Airport.

Just after a curve to the northwest, they travel on a bridge over some railroad tracks and intersect SR 78 and US 319 (East Calhoun Street).

In Aldreds, the intersection with Walden Brett Road leads to the unincorporated community of Pine Hill.

The concurrency curves due north and meets the northern end of a former portion of US 1 before crossing over the Ogeechee River.

They parallel the southeastern edge of Fort Eisenhower, then cross over Brier Creek and enter Richmond County and the city limits of Augusta.

They cross over Butler Creek, meet another former portion of US 1, and curve to the east-northeast to an intersection with Meadowbrook Drive and Barton Chapel Road.

The four highways curve slightly to the east-northeast to an interchange with US 25/SR 121 (Peach Orchard Road), which both join the concurrency.

Gordon Highway curves to the north-northeast and intersects Laney Walker Boulevard, entering downtown.

A short distance later, they travel to the east of Old Medical College and the Old Government House, then have an interchange with US 25 Bus./SR 28 (Broad Street).

[2][3] The roadway that would eventually become US 1/SR 4 was designated at least as early as 1919 as part of SR 15 from the Florida state line to Alma, an unnumbered road from Alma to Baxley, part of SR 17 from Swainsboro to Louisville, and another unnumbered road from Louisville to Augusta.

The entire highway, from the Florida state line to Augusta, had a completed hard surface.

[21][22] By June 1955, Gordon Highway was established around the southwest side of Augusta and proposed to the 5th Street/Gwinnett Street intersection.

US 25 was shifted off of Broad Street and onto Gordon Highway, which was extended to the South Carolina state line.

SR 21 was extended west-northwest on US 25 Bus./SR 28 (Broad Street) and followed the business route to the South Carolina state line.

This portion may eventually be incorporated into the proposed eastern extension of I-14, which is currently entirely within Central Texas and may be extended into Augusta.

The Georgia Department of Transportation (GDOT) will widen 21 miles (34 km) of US 1/SR 4 from north of Wadley to Wrens and will be a total of $17 million in budget.

SR 4 is completely concurrent with US 1 from the Florida state line to the main part of Augusta.