Donaghdee Lighthouse

The foundation stone of the new harbour was laid by the Marquis of Downshire on 1 August 1821. The initial plans and surveys for this ambitious undertaking had been made by John Rennie Senior, the celebrated engineer whose works included Waterloo, Southwark and London Bridges over the Thames. However, he died within two months of beginning the work, and was succeeded by his son, John, later Sir John Rennie. He had as his resident engineer a fellow Scot, the seasoned marine builder, David Logan, who had assisted Robert Stevenson at the Bell Rock Lighthouse (1807–1810).

The construction of the tower started in 1836 at the end of the South Pier. The tower was constructed in Cut Limestone tapered cylindrical tower in white with a black plinth with balcony and lantern tower (16m or 52 feet high).

A serious fire damaged the optic and lantern on the 12th May 1900 and a temporary light had to be shown whilst a new optic was obtained and the damaged lantern repaired. This was completed by September of the same year.This new optic was a 4th order fixed and occulting lens from Chance Brothers.

Conversion to unwatched electric was effected from 2nd October 1934, Donaghadee thus having the distinction of being the first Irish lighthouse to be converted to electric. Chaine Tower at Larne followed the next year and Tuskar in 1938. The character of the new light was Isophase, white every four seconds and the red sector was discontinued. The power was considerably increased from less than 1,000 to 20,000 candelas. A standby acetylene light was fitted to the lamp changer which would come into operation automatically if the lamp or electric supply should fail.

In April 1967 an automatic standby to mains generator was installed in the base of the tower, a red sector was re-established (326° to shore) and a new lamp changer with two electric lamps was fitted into the optic.
The Lighthouse is now an AIS point.