The first lighthouse in the area at Cranfield point was built in 1803 when this granite structure became unsafe it was replaced in 1823 by the Haulboline lighthouse which stands on a rocky island in the mouth of Carlingford Lough which separates Co Down from Co Louth. The original tower at Cranfield point became the victim of coastal erosion in the 1860's when it toppled onto the foreshore.

As a fog signal a bell was struck by a machine every thirty seconds, this was probably powered by clockwork, this was changed to an explosive signal in 1898, once every ten minutes, and again this was changed to a diaphone horn sounding once every five minutes in 1932. When the light became automatic in 1965 an electric horn was installed giving one blast every thirty seconds.

Despite the presence of the light many casualties have occurred in the area, close to the light on the 3rd November 1916, 94 lives were lost when the Connemara a passenger steamer of 459 tons belonging to The Clantire Steamship Co of Newry under the command of Captain Patrick O'Neill bound for Hollyhead from Grenore, was struck amidships by the Retriever a loaded collier inward bound for Newry. The Connemara sank in minutes taking with her most of the passengers and crew, the Retriever sank a short time later. The first anyone knew of the disaster was when some cattle carried as cargo on the Connemara swam ashore at Cranfield on the Co Down coast.

In later years the remains of both ships were cleared when the channel was deepened to develop the ports of Greenore in County Louth and Warrenpoint in County Down.

More information about the Connamara - Retriever disaster on the website of The Killowen Historical Society.