The A512 is a link bypassing the A1 through Dunmurray and Derriaghy, as well as linking to the M1 at Blacks Road Interchange.
Beginning on the A1 at a signalised crossroads, the A512 heads north along the dual-carriageway Blacks Road to Blacks Road Interchange, where the road TOTSOs left. Continuing as a D2, it soon TOTSOs again at a roundabout and becomes S4 with a central hatched area. After a roundabout with the B102, the road narrows, losing its hatched area. At a signalised T-junction (formerly a roundabout, the A512 TOTSOs a third time, with the A513 continuing straight on. Heading south now, the road is S2 and quickly ends on the A1 at Queensway Roundabout.