Article detailing the finding and interpretation of several systems of post-medieval warping drains, identified as cropmarks in the areas of Blyton and Laughton Commons. Warping was a system of agricultural improvement which used a network of linear banked channels to direct silt-rich river water to flood open land and deposit alluvium to improve poorer quality wind-blown sands and peats. The technique was much used from the end of the 18th century to the middle of the 19th century, particularly in north-western Lincolnshire.