This article is about the Class III road numbered C45 maintained by DfI Roads. For other roads numbered C45, see C45.
The C45 starts on the B152 in the centre of Antrim and follows Steeple Road north east out of town to meet the B518 which acts as a sort of northern relief road for the town. Straight ahead is the B532 from which the C45 continues its journey from a junction between two different hospitals: Antrim Area Hospital and Holywell Hospital. The road continues northwards and passes under the two carriageways of the M2 which bridge the road over separate bridges. From here the road becomes much more rural in character as it passes through the countryside northwards. Along the way the road passes the terminus of the western route of the C44. Eventually the road reaches Kells where it terminates on the B53 at its TOTSO south of the village centre.