Carlingford (from Old Norse Kerlingfjǫrðr 'narrow sea-inlet of the hag';[2] Irish: Cairlinn) is a coastal town and civil parish in northern County Louth, Ireland.

The Vikings invaded Ireland in the 9th Century and historical records tell that they occupied Carlingford Lough, a naturally secure bay.

Carlingford was inhabited in the 12th century by Norman knight Hugh de Lacy after laying the foundation stone for a castle on a strategic outcrop of rock.

Carlingford's strategic position on the east coast of Ireland (along with Carrickfergus and Drogheda) made it an important trading port.

Carlingford's early prosperity faltered when, in 1388, the town was burnt to the ground, by a Scots force under the command of Sir William Douglas of Nithsdale.

The increased trade encouraged a mercantile class to build in the area, the results of which can be seen today in the remains of the Mint and Taffe's Castle.

Carlingford was regarded for its green-finned oysters, which remained its main employment source, alongside herring fishing.

However, the final nail in the coffin was the desertion to open water of the prosperous herring shoals that occupied the lough by the early 18th century.

Carlingford's inability to develop a heavy industry allowed its mediaeval layout and archaeological artefacts to remain relatively intact.

In 1948 the film 'Saints and Sinners' used various locations around Carlingford including a scene at the beginning at the station of a DN&GR train arriving.