Nefyn (Welsh pronunciation: [ˈnɛvɨn] ⓘ, archaically anglicised as Nevin) is a town and community on the northwest coast of the Llŷn Peninsula, Gwynedd, Wales.

[2] The history of the area can be traced back to 300 BC with the Iron Age hillfort of Garn Boduan overlooking Nefyn.

The earliest known reference to Nefyn in documents dates from the latter part of the 11th century, when it is mentioned as a landing place of the Welsh prince, Gruffudd ap Cynan.

The old church is no longer a place of worship but houses a museum dedicated to the maritime history of Nefyn.

Since 2013, archaeologists have been investigating the area under the church and have uncovered a 13th–14th century brooch and the remains of a lady buried sometime between 1180 and 1250 in an older form of entombment called a cist grave.

Since 1929, Nefyn has played host to a Beach Mission, which runs for two weeks at the beginning of August each year.

During the Second World War, the Royal Air Force built a Chain Home radar station to the south-west of Nefyn.

A tremor in the area on 12 December 1940 was reported by the Cambrian News as having caused two fatalities including John Thomas of Nefyn who died of a heart attack.

[15][16] A further landslide on 29 October 2021 blocked vehicular access to the beach at Y Lôn Gam and the adjacent cliff path was closed.