 A series of mileposts made in cast-iron appear on the stretch of road between Aylesford and Addington; at Ditton, Larkfield, and Ryarsh.The one at Larkfield is shown on an 1862 Ordnance Survey map, and the Ditton post is shown on a similar map of 1869.Both the Larkfield and Ditton posts are classed as Class II listed buildings.