Cwm Rhondda, taken from the Welsh name for the Rhondda Valley, is a popular hymn tune written by John Hughes. It is usually used in English as a setting for William Williams' text Guide Me, O Thou Great Redeemer (or, in some traditions, Guide Me, O Thou Great Jehovah), originally Arglwydd, arwain trwy’r anialwch in Welsh. On account of a line in this English translation, the tune (and hymn) is often called Bread of Heaven. In Welsh the tune is most commonly used as a setting for a hymn by Ann Griffiths, Wele'n sefyll rhwng y myrtwydd.