Porthmadog is a small harbour town on the edge of Snowdonia, where the mountains give way to the Glaslyn estuary and the coast of the Llŷn Peninsula. It grew from William Madocks' embankment and the slate trade, and the old wharf story still matters because the narrow-gauge railways now bring travellers back into the slate valleys.
The town itself is modest, but the setting is strong. Steam trains leave from Harbour Station, Black Rock Sands spreads just west of town, and Portmeirion is close enough for an easy side trip.
Porthmadog is one of the better spare-day bases in North Wales. You can spend the morning on the Ffestiniog Railway, walk the coast toward Borth-y-Gest, and still have time for beach air or Portmeirion's theatrical village design.