The B179 is an L-shaped road in Walthamstow. The road was originally unclassified but gained its present number in the mid-1930s.
The road starts at traffic lights by Blackhorse Road tube station. That name is taken from the A1006, which heads south, whilst the A503 is also met here. The B179 heads north along Blackhorse Lane, passing housing and light industry before deciding to be residential. Presently the road bears sharply right to start heading eastwards, becoming Billet Road. There are a couple of mini-roundabouts with unclassified roads before the B179 ends at the Crooked Billet Roundabout, where it meets the A406 North Circular and the A112.