Start at centre of BT manhole on A18 0.25 mile east of Great Limber. Proceed on A18 through Riby crossroads (3.3 miles) to Laceby roundabout (junction with A46) (5.4 miles). Encircle roundabout and retrace through Riby crossroads (7.5 miles) to finish opposite middle drain gully in lay-by on A18, 0.75 mile east of the start.