This circuit is mostly on public footpaths / bridleways, but there is some minor road involved. See SGB 01 ~ Shamley Green Bipedal-motion for details.
This cache is a fake rock and is accessible without damaging the hedge and should be replaced neatly tucked in.
The footpath from SGB 17 to SGB 16 forks right up a slight slope past a large brick barn/garage on the right.
The route from SGB 17 to SGB 18 involves 150m along the busy, no footpath, B2128 (past the site of The long and winding road Stage 4). I seriously recommend keeping children under tight control along here, walk on the right side of the road to face oncoming traffic, and carry a light bright object in the day or torch at night to hold slightly out from your body to the left to make it easier for cars to see you. The destination footpath is opposite the apparent end of the brick wall on the west side of the road where it kinks east about 1m.
Good hunting. You may also be interested in my other caches.