Holyhead is the largest town on Holy Island, Anglesey. It is a major seaport, boasting a ferry link with Ireland over 200 years old. Although Holyhead remained a comparatively small fishing village until around 1800, the area was settled as far back as the Neolithic era, as can be seen in the many remains of circular huts, burial chambers and standing stones. In the fourth century, a Roman military outpost was established here and in the sixth century the abandoned camp was repurposed, with a church and monastery dedicated to St Cybi. The Welsh name of Holyhead, Caergybi (‘Cybi’s fort’), neatly summarizes both its Roman and early Christian origins.

Since at least since the seventeenth century, Holyhead has served as north Wales’s main port for sailing to Ireland. The completion of Thomas Telford’s post road, the opening of his Menai Suspension Bridge, and the arrival of the railway in the first half of the nineteenth century considerably boosted the growth of the town. In 1819, the first steam ships were employed in the transport of mail and passengers between Holyhead and Kingstown (Dún Laoghaire), making the service more reliable and increasing the traffic across the Irish Sea. It therefore became necessary to develop a new, much larger harbour able to give refuge to up to 1000 ships in the event of bad weather. The result was the construction of Holyhead breakwater, which at 2.7km remains the UK’s longest seawall.