This article is about the Class III road numbered C57 maintained by DfI Roads. For other roads numbered C57, see C57.
The C57 is another rather lengthy C road in mid County Antrim. At its southern end it has two starting points: one from the A26 just south of its junction with the M2 to the north of Ballymena and the other from the B62 in Cullybackey. Both branches head north to meet each other at a crossroads, with the eastern branch continuing ahead towards the B93 just over the River Maine. From here the road continues to meander its way north west and eventually crosses the B64. Just beyond crossing the B64, the route turns off to the north and after some distance turns off to the right at a crossroads. The road ends on the B16 just to the east.