Map - Dún Laoghaire (Dún Laoghaire)

Dún Laoghaire is a suburban coastal town in Dublin in Ireland. It is the administrative centre of Dún Laoghaire–Rathdown. The town was built up alongside a small existing settlement following 1816 legislation that allowed the building of a major port to serve Dublin. It was known as Dunleary until it was renamed Kingstown in honour of King George IV's 1821 visit, and in 1920 was given its present name, the original Irish form from which "Dunleary" was anglicised. Over time, the town became a residential location, a seaside resort, the terminus of Ireland's first railway and the administrative centre of a borough and then a county.

The town's name means "fort of Laoghaire". This refers to Lóegaire mac Néill (modern spelling: Laoghaire Mac Néill), a 5th century High King of Ireland, who chose the site as a sea base from which to carry out raids on Britain and Gaul. Traces of fortifications from that time have been found on the coast, and some of the stone is kept in the Maritime Museum.

The name is officially spelt Dún Laoghaire in modern Irish orthography, and in general usage. It is sometimes unofficially written as Dún Laoire. The old anglicised spelling Dunleary is also seen. This last is how the town's name is commonly pronounced, although the Irish pronunciation is also common.