Nicholas Treweek's shipyard is the first recorded at Amlwch and in part utilsied a quay which may date back to the first copper exports during the reign of Elizabeth I. Small amounts of shipbuilding activity had taken place on the western side of the harbour prior to 1825, but Nicholas Treweek established a yard employing 32 men when he was commissioned by his father James to build a 68nt sloop called the UNITY in 1825. The yard continued in his name until business was transferred to new dry dock after 1858 (NPRN 41246). The yard was sold to William Cox Paynter (for the family's sawmill see NPRN 417394) who concentrated more on repair than building. William Cox Paynter died in 1884 and the yard continued under the direction of Captain Thomas Morgan. The range of buildings (possibly up to 10) associated with yard are shown on 1st-3rd edition OS mapping. The launching/hauling out slip enters the habrour near to the baulks (SH44979340). A crane is situated on the quay nearby. Modern aerial photography shows that part of the range at the rear of the yard is still extant but roofless (SH44949340).

Sources include:
NAW aerial photography 2006-9
OS 1st-3rd edtion 25in mapping

Maritime Officer, RCAHMW, August 2012.