Pwllheli is a market town and community on the Llŷn Peninsula, north-west Wales. It lies in the traditional county of Caernarfonshire but is curren…Pwllheli is a market town and community on the Llŷn Peninsula, north-west Wales. It lies in the traditional county of Caernarfonshire but is currently administered as part of the unitary authority of Gwynedd. It had a population of 4,076 in 2011, the population declining slightly to 3,947 in 2021. of whom a large proportion, 81%, were Welsh speaking. Pwllheli is the place where Plaid Cymru was founded. It is the birthplace of the Welsh poet Sir Albert Evans-Jones.