Start in the large gate entrance on the west side of the A6055, 0.3 miles north of the A684 roundabout (part of A1M Junction 51), at the most northern of two adjacent grates. Join the A6055 and proceed north towards Catterick. After 2.38 miles cross over the A1M on the high-rise bridge. After 4.6 miles take care while passing the junctions to Catterick / Marne Barracks and Tunstall. Continue to the Pallett Hill roundabout (part of A1M Junction 52), at 5.63 miles. Encircle the roundabout and return south back along A6055. After 6.70 miles again take care while passing the junctions to Tunstall and Catterick / Marne Barracks, to cross over the A1M on the high-rise bridge at 8.93 miles. Continue to finish at the southern end of the manhole cover in the east side verge of the A6055, 10.0 miles. (340 yards south of the gate on the west side with the “Access to Pollution Valve” sign, and 1.28 miles north of the start.)