Road accident data on a section of the A487 between Penrhyndeudraeth and Trawsfynydd between the A496 and A470 junctions, 2011-2016
Data am ddamweiniau ffyrdd ar ran o'r A487 rhwng Penrhyndeudraeth a Thrawsfynydd rhwng cyffyrdd yr A496 a'r A470, 2011 i 2016