This detailed map continues our coverage of the Rhondda Valley. It covers much of the village of Gelli, including parts of Ton and Ystradyfodweg. Coverage stretches from Gelli Road southward to Mynydd Bwllfa, and from Maendy Pit eastward to Gelli Collieries. Features include Taren y Bwllfa, Eastern Pit with tramway, Bwllfa Ddu Level with tramway, part of Maendy Pit, Gelli Collieries, various quarries. On the reverse we include a directory of Ton or Ton Pentre.
The map links up with Glamorgan sheets 18.14 Pentre to the north and 27.03 Llwynypia to the east.