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Page 108. " Because the stronghold, on the other hand, was built by a host of men it is called Caerfyrddin "

The Welsh word ‘myrddin’, meaning ‘host’, is a component of Caerfyrddin (the Welsh name for Carmarthen in southwest Wales). It has also been suggested that the name Caerfyrddin is linked to the wizard Merlin who is known as Myrddin in Welsh. Generally, however, it is believed  that both these suggestions are wrong and that the name Caerfyrddin derives from Maridunum or Moridunum, a Roman fort which stood on the site of present-day Carmarthen.