Holy Island, Anglesey in the context of "Isle of Anglesey"

Anglesey (/ˈæŋɡəlsi/ ANG-gəl-see; Welsh: Ynys Môn [ˈənɨs ˈmoːn]) is an island off the north-west coast of Wales. It forms the bulk of the county known as the Isle of Anglesey, which also includes Holy Island (Ynys Gybi) and some islets and skerries. The county borders Gwynedd across the Menai Strait to the southeast, and is otherwise surrounded by the Irish Sea. Holyhead is the largest town, and the administrative centre is Llangefni.

The Isle of Anglesey has an area of 275 square miles (712 km) and had a population of 69,097 in 2024. After Holyhead, located on Holy Island, the largest settlements are Llangefni in the centre of Anglesey and Amlwch on the northern coast. The economy of the county is mostly based on agriculture, energy, and tourism, the latter especially on the coast. Holyhead is also a major ferry port for Dublin, Ireland. The county has the second-highest percentage of Welsh speakers in Wales, at 57.2%, and is considered a heartland of the language. The Isle of Anglesey is part of the preserved county of Gwynedd.

Holyhead (/ˌhəʊliˈhɛd, ˌhɒliˈhɛd/; Welsh: Caergybi pronounced [kɑːɨrˈɡəbi] , "Cybi's fort") is a historic port town, and is the largest town and a community in the county of the Isle of Anglesey, Wales. Holyhead is on Holy Island, bounded by the Irish Sea to the north, and is separated from Anglesey island by the narrow Cymyran Strait, having originally been connected to Anglesey via the Four Mile Bridge.

In the mid-19th century, Lord Stanley, a local philanthropist, funded the building of a larger causeway, known locally as "the Cobb"; it now carries the A5 and the railway line. The A55 dual carriageway runs parallel to the Cobb on a modern causeway.

The Port of Holyhead (Welsh: Porthladd Caergybi) is a commercial and ferry port in Anglesey, United Kingdom, handling more than 2 million passengers each year. It covers an area of 240 hectares, and is operated by Stena Line Ports Ltd. The port is the principal link for crossings from north Wales and central and northern England to Ireland. The port is partly on Holy Island and partly on Salt Island (Welsh: Ynys Halen). It is made up of the Inner Harbour, the Outer Harbour and the New Harbour (opened in 1880), all sheltered by the Holyhead Breakwater which, at 2.7 kilometres, is the longest in the UK.