[Afon] Celyn (Topographic feature).
Grid Reference: SH 83878 42317. Parish: Llanycil, Merionethshire
When recorded: 1699. Primary Source: Parochialia 2. Secondary Source: none

Afon Celynog (Unclassified).
Grid Reference: SH 80237 20153. Parish: Brithdir and Islawr-dref, Merionethshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt Llwyn-celyn (Unclassified).
Grid Reference: SN 59442 32547. Parish: Talley, Carmarthenshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt Llwyn-celyn (Unclassified).
Grid Reference: SN 50677 30833. Parish: Llanfihangel Rhos-y-corn, Carmarthenshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt llwyn-celynen (Unclassified).
Grid Reference: SN 02525 34150. Parish: Llanychlwydog, Pembrokeshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt Llwyn-y-celyn (Unclassified).
Grid Reference: SN 60282 23756. Parish: Llangathen, Carmarthenshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt Pistyll-celyn (Topographic feature).
Grid Reference: SN 52360 20054. Parish: Llanarthne, Carmarthenshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Allt-y-celyn (Unclassified).
Grid Reference: SJ 14486 42368. Parish: Corwen, Merionethshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Banc Celynog (Unclassified).
Grid Reference: SN 70397 23652. Parish: Llangadog, Carmarthenshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website

Banc y Celyn (Unclassified).
Grid Reference: SO 04534 46460. Parish: Gwenddwr, Brecknockshire
When recorded: 1898-1908. Primary Source: OS 2nd Edition Maps. Secondary Source: GB1900 website