New Road bridge, Northchurch
The B4506 is a largely rural B-road in the Home Counties. It was originally unclassified but gained its number in the early 1930s.
The road starts by turning off the A4251 (pre-bypass A41) in Northchurch, a suburb of Berkhamsted and heads north along New Road. There's a narrow bridge over the Grand Union Canal, then we climb to leave town. There's a sharp left-hand bend on the edge of the wooded Northchurch Common, then we cross the common and pass through a clearing to enter Berkhamsted Common.
We pass the National Trust's Ashridge Common and a golf course before reaching Ringshall. On the far side of the small village we enter open country and then descend via a couple of tight bends to Dagnall, where we cross the A4146 at a roundabout. We continue north along the foot of a ridge before bearing left to move away. The B4540 comes in from the right, then we end a short distance further on at a roundabout on the B489.