A sunken lane is a road or track that is significantly lower than the land on either side, not formed by the engineering of a road cutting but possibly of much greater age.
Various mechanisms have been proposed for how holloways may have been formed, including erosion by water or traffic; the digging of embankments to assist with the herding of livestock; and the digging of double banks to mark the boundaries of estates. These mechanisms are all possible and could apply in different cases.
Wikipedia https://en.wikipedia.org/wiki/Sunken_lane
Address 79359, Germany
Coordinates 48°8'38.48" N 7°44'12.804" E