State Route 154 begins at SR 54 in Sharpsburg and ends at SR 10 (Memorial Drive/Cynthia McKinney Parkway) just to the east of Avondale Estates.

State Route 154 intersects with State Route 34 just west of Peachtree City and continues north where it crosses I-85 at exit 51. Less than a mile north, SR 154 turns north and joins with US 29/SR 14 until north of Palmetto where it turns (And gets the name Cascade-Palmetto Highway) and crosses South Fulton Parkway and joins with SR 70. Cascade-Palmetto Highway (State Route 70/State Route 154). SR 166 joins SR 154 just a little bit later. Campbellton Road (SR 166/SR 154) crosses Camp Creek Parkway (State Route 6), entering the Sandtown community on its way to the Ben Hill community.

SR 166/SR 154 leaves the Ben Hill community as Arthur B. Langford Jr. Parkway. Langford Parkway, is a limited access freeway that was originally named the Lakewood Freeway and was planned as Interstate 420. It continues into East Point, passing the Fort McPherson Army base. SR 154 leaves Langford Parkway at Main Street (U.S. Route 29/State Route 14/State Route 139).