AbstractA series of facies distribution maps with accompanying discussion is given for nine divisions of the Ludlovian; significant information on faunas and sedimentary features is incorporated. Isopachyte maps are presented for the whole of the Ludlovian and for its four component stages. Two sections are drawn across the area of sedimentation from northwest to southeast and northeast to southwest respectively. From the evidence assembled in these maps and sections deductions are made as to the probable palaeogeography of the Welsh Borderland area in Ludlovian times.