From its junction with the M9 it heads east to the former N9. It crosses this at a staggered junction and enters County Wicklow almost immediately and southeast it crosses the N81 in the town of Baltinglass. It continues southeast through Kiltegan before crossing into County Carlow for a short distance where it passes through Hacketstown. Back in County Wicklow it crosses the Wicklow Way and enters the southern end of the Wicklow Mountains near Tinahely.