The first sections complete and open to traffic extended east of US 41 and included the interchanges with then-new I-75, and with mainline SR 120.

Northwest of Manget Street, the highway went diagonally through existing neighborhoods, again destroying several homes.

Work began again in the early 1980s to complete most of the northern quadrant when the roadway was extended from the previously-mentioned diamond interchange to connect to and take over Page Street.

This portion took out the Williams Brothers Lumber Company, and involved building an entrenched roadway with an overpass for Kennesaw Avenue (the original US 41 and SR 3) and the L&N Railroad, with the roadway tying into the extension of the new Powder Springs Street, which previously ended at Polk Street.

In addition, SR 5 was relocated out of downtown Marietta onto part of the new loop to the west; it was later rerouted through a completely different city, going down Austell Road instead of Powder Springs Road, and may be rerouted yet again off of the loop and completely away from Marietta onto Barrett Parkway.

SR 5 currently shares the west end of the Loop, west from Cherokee Street (northbound only) to Church Street (southbound only), southwest to Whitlock Avenue, south to Powder Springs Road, and turning east at that intersection to Atlanta Road.

Along the west side from Whitlock Avenue south to the "new" Powder Springs Street, then east to Atlanta Road, southeast to Manget Street, east to I-75, then northeast to Lower Roswell Road, it is known as South Marietta Parkway.

Almost all of it is in the county's southeast quadrant for street addresses, except west of the railroad tracks where it is southwest.

Its main purpose is as a bypass route around the central business district of Marietta, like most loop roads.