In the early 13th century a town called Llanfaes in the south-east corner of Anglesey grew up under the patronage of Llywelyn the Great.
Tua dechrau’r 13eg ganrif, tyfodd tref o’r enw Llanfaes yng nghornel de-ddwyrain Ynys Môn o dan nawdd Llywelyn Fawr.