I-75 is the only Interstate to traverse the full length of the state from north to south, from the flat Atlantic Coastal Plains in southeast Georgia to the rolling mountains of North Georgia.

The segment from SR 49 in Byron to I-16 in Macon is part of the Fall Line Freeway and may be incorporated into the eastern extension of I-14, which is currently entirely within Central Texas and is proposed to be extended to Augusta.

[1] It enters the state near Valdosta, and it continues northward through the towns of Tifton and Cordele until it reaches the Macon area, where it intersects with I-16 eastbound toward Savannah.

For northbound traffic, I-475 provides a relatively straight bypass west of that city and I-75's route.

It crosses inside the Perimeter and heads north several miles toward the Atlanta city center.

I-75 then runs concurrently with I-85 due north over the Downtown Connector through the central business district of Atlanta.

This section of I-75 just north of I-285 has 16 through lanes, making it the widest roadway anywhere in the Interstate Highway System.

[4] North of Marietta, the final major junction in the Atlanta metropolitan area is the I-575 spur.

I-75 then traverses the hilly North Georgia terrain as it travels toward Chattanooga, Tennessee.

[citation needed] Due to recent lane widening in southern Georgia completed in 2011,[5] the only four-lane section of I-75 in Georgia is bypassed by six-lane I-475; along this route, there are at least six lanes from the Alligator Alley portion of I-75 in Naples, Florida, to a portion of I-75 in Ooltewah (except a four-lane overpass on I-475 over a railroad track in Macon).

The section that would become US 41, I-75's direct predecessor, from Echeconnee south through Perry and Valdosta to the border with Florida was paved beginning in 1919 and was later designated as a part of the Dixie Highway in 1924.

[16] The highway that would eventually become I-75 in Georgia was an unnamed expressway that was open in 1951 from the southern part of Atlanta to University Avenue.

This expressway was open from Williams Street to what is now the northern end of the Downtown Connector.

It was under construction from the Downtown Connector to US 41/SR 3E, just north of West Paces Ferry Road.

It was open from Forest Park to West Paces Ferry Road in northwest Atlanta.

[3][23] In 1966, the highway was open from the Florida state line to its southern interchange with I-475 near Macon.

Construction began with widening I-285 first, beginning in 1976, continued to the radiating expressways, and concluded with the depressed sections of the Downtown Connector which were completed in 1988.

[citation needed] In 1998, the portion of I-75 that from the Chattahoochee River north to the Tennessee state line was named the Larry McDonald Memorial Highway.

[36] Larry McDonald, a conservative Democratic representative to Congress, was aboard Korean Air Lines Flight 007 when it was shot down by the Soviet Union on September 1, 1983.

][citation needed] Until 2000, the state of Georgia used the sequential interchange numbering system on all of its Interstate Highways.

[40] On September 8, 2018, new Northwest Corridor Express Lanes from the I-285/I-75 interchange to Hickory Grove Road and from I-75/I-575 interchange to Sixes Road have opened, the lanes require a Peach Pass to use.

The segment of I-75 from SR 49 in Byron to I-16 in Macon is part of the Fall Line Freeway and may be incorporated into the eastern extension of I-14, which is currently entirely within Central Texas and is proposed to be extended to Augusta.

[43] Note: exit numbers along Georgia Interstates were renumbered in 1999 and 2000 to be mileage based instead of being sequential.