Here are the details of maps for Portmadoc:
This detailed map of Porthmadog (or Portmadoc) is double-sided for maximum coverage. The main map covers most of the town in detail, with individual buildings neatly shown; coverage extends eastward to Afon Glasslyn and southward toBron-y-garth. Features include Ffestiniog Railway with station, Croesor Tramway, New Wharf, Dock, Slate Wharf, Ballast Bank, Garth, St John's church, Tuhwnt-i'r-bwlch, The Park, Ynys Tywyn, High Street area, Llyn Bach, Town Hall, North Wales Slate Works, chapels, Bron-y-garth, etc. (NB. Cambrian Railway is on Tremadog map.)
On the reverse we include about half of adjacent sheet 35.13 extending coverage eastward to Minffordd. Features here include Minffordd Junction station with transhipment sidings, GartbQuarry, Boston Lodge Railway Works, Ffestiniog Railway, cemetery.
The map links up with sheet 34.12 Tremadog to the north.