St Cybi was a sixth-century Welsh saint whose name now anchors a town of 12,084 people. The Welsh call it Caergybi - Cybi's Fort - because the medieval church he founded was built inside the walls of an existing Roman fort, an unusual three-walled enclosure with the fourth side opening directly onto a sea that has since retreated. The English have called it Holyhead since at least the fourteenth century, a name that signals the density of sacred sites at this far western edge of the island. Roman fort, medieval saint, Iron Age hillfort on the mountain behind, prehistoric standing stones in every direction - the whole point of Holyhead, before it became the point at which Britain catches the boat to Dublin, was its strangeness as a place where many overlapping holinesses had accumulated on a small bit of land.
St Cybi's Church is built inside one of the few three-walled Roman forts in Europe. The Romans did not need a fourth wall: the sea came right up to that side, doing the job of fortification for them. The sea has since pulled back, leaving the fort high and dry, but the missing wall is a small architectural anomaly that has survived in plain sight for nearly two thousand years. On the summit of Holyhead Mountain a couple of miles west, the Romans built a watchtower inside the much older prehistoric hillfort of Caer y Twr - again reusing a structure that was already old when they arrived. Holyhead Old Town developed around the church, which developed around the fort. The town's English name refers to the holiness of the locality. The Welsh name credits the saint who arrived in the middle of all of it.
The 1800 Acts of Union, which merged the Irish and British parliaments, made the London-Dublin route a national priority. By 1814, passenger traffic between Holyhead and Dublin had reached around 14,000 a year. The South Stack Lighthouse was lit in 1809. Thomas Telford built the London-Holyhead Road - now the A5 - culminating in the Admiralty Arch at Salt Island, designed by Thomas Harrison to commemorate the visit of George IV in 1821 on his way to Dublin. The Chester and Holyhead Railway opened in August 1848. The Holyhead Breakwater, the longest in the UK at 1.7 miles, took twenty-eight years to build and opened in 1873. The breakwater used seven million tons of quartzite from Holyhead Mountain. Across the same period, a hierarchy of British engineers - Rennie, Telford, Stephenson, Rendel - poured their best work into the simple problem of getting British post and people across to Ireland on schedule.
From 1971 to September 2009, Holyhead's main industry was the Anglesey Aluminium smelter on the edge of town. Ships arrived from Jamaica and Australia carrying alumina, which travelled to the plant on a rope-driven conveyor belt running under the town from a dedicated jetty. The smelter needed enormous electricity supplies, drawn from the Wylfa nuclear power station up the coast at Cemaes Bay. When Wylfa wound down toward closure in 2015, the smelter closed first - the economics no longer worked. Until 2020, Holyhead was the second-busiest roll-on roll-off port in the UK after Dover, with around 450,000 lorries a year on the Dublin run. The Brexit withdrawal agreement cut Irish-British freight traffic by fifty percent in January 2021. The port survives, and in December 2024 it was knocked offline for weeks when two ferries collided with a berth during Storm Darragh - reopening partially in January 2025 and only fully later that summer.
Dawn French, half of the French and Saunders comedy partnership and star of The Vicar of Dibley, was born in Holyhead in 1957. The Welsh poet and Anglican priest R. S. Thomas grew up in the town. Glenys Kinnock, the politician and MEP, was educated at Holyhead High School - which, when it was reorganised in 1949, was the first comprehensive school in the United Kingdom. Linguist David Crystal lives here, as does his son the actor Ben Crystal. Cledwyn Hughes, who became Baron Cledwyn of Penrhos, was a Labour minister and another product of the town's schools. According to recent censuses, around half the people in Holyhead can speak Welsh - the highest proportion in the 15-year-old age group, where two-thirds of the children are bilingual. Caergybi, the saint's town, has stayed Welsh-speaking even as its English-speaking ferry traffic kept arriving century after century.
On 23 November 1981, Holyhead was struck by two tornadoes during the largest tornado outbreak ever recorded in the United Kingdom. One hundred and four tornadoes touched down across the country that day, and the strongest of all of them - rated F2 on the Fujita scale - hit Holyhead, damaging around twenty properties and destroying a mobile home. Maritime climate gives the town cool summers and mild winters and the chronic high winds you would expect from a port on the Irish Sea. The nearest official weather station is at RAF Valley, the active fighter base about five miles southeast of the town. Most days the weather is dramatic without being extreme. The 1981 tornado was the exception that proved the maritime rule: when the Atlantic decides to do something unusual at this corner of Wales, it does it at scale.
Holyhead sits at 53.32N, 4.63W on the eastern side of Holy Island, with the Port of Holyhead and the long curve of the Holyhead Breakwater dominating the northern shore. The town extends south and east from the inner harbour, with the railway station and ferry terminal at the harbour's southern end. Holyhead Mountain (722ft) is the prominent terrain feature to the west. The Stanley Embankment causeway carries the A5 and the railway across the Cymyran Strait to Anglesey proper. Nearest airfields: RAF Valley (EGOV) 6nm southeast, Caernarfon (EGCK) 20nm southeast. Best viewed at 2,000-3,500ft AGL for full town and harbour perspective. Surface winds can be strong from the west.