Information sheets on the following collieries can be found within this file (please note that the amount of information on each sheet varies):
Aber (drift)
Aberaman
Aberavon
Aberbaiden
Aberbeeg South and Aberbeeg North
Abercanaid
Aber Rhondda
Abercarn (Prince of Wales)
Aberclwyd
Abercrave
Abercrave International Slant
Abercwmboi
Abercynon (or Dowlais-Cardiff)
Aberdare Graig
Aberdulais
Abergelli
Abergorchi Drift
Abergorki
Abergorky (somethimes known as Abergorki)
Abergwawr
Abernant (Aberdare)
Abernant (Pontardawe)
Abernant (Sirhowy)
Aberpergwm
Abertillery (Rose Heyworth)
Abersychan
Achddu
Acron (Slant)
Adare
Albion
Albion Road (Slant)
Amman (Slant)
Ammanford No.1 (Old Betws Mine)
Ammanford No.2
Anthony
Ann
Arall (or Arail)
Argoed
Argoed Level
Arrail Griffin 4 and 5
Avon (Ocean)
Avon Merthyr