State Route 280 (SR 280) is a south-north state highway located in the Atlanta metropolitan area in the west-central part of the U.S. state of Georgia. It runs from SR 139 in western Atlanta to Interstate 75 (I-75) in Marietta.

SR 280 begins in western Atlanta at an intersection with SR 139 (Martin Luther King Jr. Drive), where the roadway continues as Hamilton E. Holmes Drive. The route travels north along Hamilton E. Holmes Drive and James Jackson Parkway, meeting I-20 at an interchange, then continues north to an intersection with US 78/US 278/SR 8 (Donald Lee Hollowell Parkway). Then, the route continues on to the Atlanta neighborhood of Riverside, where the route curves to the northwest. It then crosses the Chattahoochee River into Cobb County, where it is known as South Cobb Drive. The route continues northwest until its an interchange with I-285 in Smyrna. SR 280 passes through western portions of Smyrna. In Fair Oaks, the route begins a short concurrency with SR 5. After arcing to the northeast, SR 5 departs the concurrency. SR 280 then curves to the southeast, passing through Dobbins Air Reserve Base, and then to the east to an intersection with US 41/SR 3. There, it becomes known as Delk Road. The route heads nearly due east until it meets its northern terminus at I-75, exit 261 in Marietta, where the roadway continues as Delk Road.

The route has at least four lanes for its entire length, and has 6 lanes in Marietta and between US 41 and I-75.[citation needed]

SR 280 is a major urban arterial, with portions of the route seeing an Average Annual Daily Traffic (AADT) of over 30,000 vehicles, especially around Dobbins Air Reserve Base. It serves as a major commuter route in southern Cobb County and for those traveling to Dobbins Air Reserve Base and the Lockheed-Martin plant in Marietta.

In northwest Atlanta, SR 280 was known as Hightower Road, but was renamed to honor Hamilton E. Holmes.[citation needed]