START (GR 499958) at Stapleford Abbotts on the B175, at the junction with Hook Lane, at the northern end of the bus lay-by (at third kerb joint from broken paint line which indicates kerb line across Hook Lane. Proceed north along B175 and A113 to Marden Ash roundabout (5.48m), where turn WITH CARE (M & C). Retrace along A113 and B175 to FINISH (503973) at drain grid past entrance to telephone exchange, which is 45 yards past L.P.1 at centre of bus lay-by immediately after Passingford Bridge.