Dan arweiniad Cyngor Gwynedd, mae’r dynodiad hwn yn benllanw dros 15 mlynedd o waith caled gan bartneriaid, gan gynnwys Cadw, i gofnodi, diogelu a chydnabod gwaddol byw tirwedd lechi Gwynedd.
Led by Gwynedd Council, the inscription is the culmination of over 15 years of hard work by partners including Cadw to record, safeguard and recognise the living legacy of the slate landscape of Gwynedd.