|Length:||12.8 miles (20.6 km)|
|Meets:||A4, B4001, A419, A4259|
|Route outline (key)|
The road starts on the A4 on the northern edge of Hungerford and heads northwest out of town along the valley of the River Kennett. Presently the road bends sharply right, crosses almost the entire valley bottom (including the river) and then bends sharply left on entering Chilton Foliat to continue its journey upstream. The B4001 turns off in the village centre.
The road continues across the fields in the valley bottom for another mile or so to reach Knighton, where it bears right to follow a small tributary. This takes us into Aldbourne where we zigzag through the village streets before climbing up onto the downs to the northwest. The road is tree-lined for some of this distance.
We descend to cross the Wessex Ridgeway and then the M4, which is in cutting at this point, with Swindon visible ahead. Liddington is then bypassed; the bypass is an old one and the church and village hall but few other buildings lie on the wrong side. The road soon levels out and ends at a roundabout on the A419 bypass. The A4259 continues ahead along the old road into town.