Porthmadog is a small coastal town located in Caernarfonshire in north Wales, with a population of around 4,000.
Located on the Irish Sea coast, Porthmadog has a small harbour where ships used to load with slate carried from the Ffestiniog Railway, of which Porthmadog is the southern terminus. Porthmadog is also the terminus of the Welsh Highland Railway.
Nearby Porthmadog is Portmeirion, where the 1960s television series The Prisoner was filmed.