Below is a listing of the first known reference in newspapers to cricket being played by teams starting with the letter A in various settlements in Wales during the 19th century.
Aberaeron 1850
Aberaman 1854
Aberaman Church Lads Bridgade 1896
Aberamman Juveniles 1863
Aberamman Powell Duffryn 1875
Aberamman St Elvans Church 1883
Aberavon 1876
Aberavon Athletic 1897
Aberavon Intermediate School 1899
Aberavon Lads Brigade 1897
Aberavon YMCA 1898
Aberbeeg 1896

Credit – Glamorgan Cricket Archives.
Abercarn 1855
Abercarn Good Templars 1874
Abercarn Juniors 1867
Abercynon 1898
Aberdare (see Aberdare)
Aberderfyn 1869
Aberdovey 1874
Aberdovey and Towyn 1879
Aberdovey Visitors 1899
Aberdulais 1879
Aberdyfi 1834
Abergavenny 1834

Credit – Glamorgan Cricket Archives
Abergavenny Early Closing Club 1865
Abergavenny Commercials 1866
Abergavenny Grammar School 1859
Abergavenny Juniors 1886
Abergavenny Morning Club 1861
Abergavenny /Hereford Railway 1866
Abergavenny Volunteers 1866
Abergele 1883
Abergwili 1872
Abergwili National School 1860
Aberia 1885
Abermorlais School 1875
Aberpergwm 1895
Abersoch 1877
Abersychan 1866
Abersychan Ironworks 1866
Abertha 1897
Abertillery 1850

Credit – Glamorgan Cricket Archives.
Abertillery Juniors 1890
Abertillery Juveniles 1874
Abertillery Methodists 1898
Abertillery Primitives 1899
Abertillery Wednesdays 1894
Abertillery Wesleyans 1898
Aberystwyth (see Aberystwyth)
Acrefair 1876
Ael-y-Bryn 1897
Afan 1864
Afon Wen 1882
Agincourt (Monmouth) 1864
Albert (Wrexham) 1867
Albion (Cilfynydd) 1891
Albion (Wrexham) 1867
Allensmore 1861
Amlwch 1867
Amman 1875
Ammanford 1889
Ammanford Nomads 1893
Angle 1859
Anglesey (Gentlemen of) Anglesey 1854
Anglesey 1852
Anglesey Collegiate School 1861
Anglesey Visitors 1899
Argyle 1897