Cantref Arfon
Coordinates: 53°04′59″N 4°00′00″W / 53.083°N 4.000°W
The mediaeval Welsh cantref of Arfon in north-west Wales was the core of the Kingdom of Gwynedd. Later it was included in the new county of Caernarfonshire, together with Llŷn and Arllechwedd under the terms of the Statute of Rhuddlan in 1284. The island of Anglesey faced it across the Menai Strait; to the east was the cantref of Arllechwedd, to the south the cantref of Eifionydd (which, together with Ardudwy, was part of the earlier kingdom of Dunoding), and to the west was the cantref of Llŷn.
As the name suggests, Arfon faces Anglesey (Môn) (see soft mutation) across the Menai, and controls access to that strategic strait which has played an important part in Welsh history. Broadly speaking, it stretched from the peaks of Yr Eifl in the west to Afon Cegin, a stream just east of Bangor, and inland from the shores of the Menai southwards into the heart of Snowdonia (Eryri), including Dyffryn Nantlle and the strategic Llanberis Pass.
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