1. 1939

    Ysgol Lluest, Aberystwyth - The Urdd open Wales’s first designated Welsh medium school

  2. 1947

    Ysgol Gymraeg Llanelli – First Welsh medium school opened under the Education Authority

  3. 1949

    Ysgol Gymraeg Glanrafon, Mold (January)

  4. 1949

    Ysgol Dewi Sant, Rhyl (January) – Rhyl was part of the old Flintshire

  5. 1949

    Ysgol Gymraeg Gwenffrwd, Holywell (May)

  6. 1950

    Ysgol Gymraeg Coed Talon

  7. 1952

    Ysgol Gymraeg Terrig, Treuddyn (pupils form Ysgol Coed Talon transfer to Ysgol Terrig, Treuddyn)

  8. 1954

    Ysgol Gymraeg Mornant (Ffynnongroyw originally before moving to Gwesbyr/Picton)

  9. 1956

    Ysgol Uwchradd Glan Clwyd, Rhyl – First Welsh medium high school opened in Wales (Rhyl was part of the old Flintshire) 

  10. 1961

    Ysgol Uwchradd Maes Garmon, Yr Wyddgrug

  11. 1964

    Ysgol Gymraeg y Fflint (Ysgol Croes Atti since 1987)

  12. 2014

    2014 - Ysgol Croes Atti Glannau Dyfrdwy, Shotton