The earliest surviving collection of the Welsh Triads is bound in the manuscript Peniarth 16, now at the National Library of Wales, which has been dated to the third quarter of the 13th century and contains 46 of the 96 triads collated by Rachel Bromwich.
A colección máis antiga das Tríades galesas está ligada ao manuscrito Peniarth 16, actualmente na Biblioteca Nacional do País de Gales, que foi datada do terceiro trimestre do século XIII e que contén 46 das 86 tríades editadas por Rachel Bromwich.