St John’s Point Lighthouse (Saint Johns Point)

The improvement of the nearby harbour at Killough n the late 18th and early 19th centuries had hastened the need for a beacon at what had long been regarded as an exposed and treacherous part o the east-Ulster coast (see Harris above) Construction of the lighthouse was approved by the Ballast Board in 1839 (officially the Corporation for Preserving and Improving the Port of Dublin), with Capt. P. R. Browne, from a leading gentry family in the locale, acting as building contractor. The Marquis of Downshire laid the foundation stone. The station consisted of a white 45 foot high tower and two small houses. On 1 May 1844, the light was established with a range of 12 mi (19 km). The area received international intention for the first time when, in 1846 and during her second season of service and not long after embarking for New York, the then largest vessel afloat, Great Britain made a series of navigational errors that resulted in her being run hard aground in Dundrum Bay just down the coast from St. John's point on 22 September. There was no formal inquiry but her Captain, James Hoken, is reported to have mistook the new St John's light for the Calf light on the Isle of Man, leading the then largest ship in the world to beach on the shore just west of St. John's point on the Down coast.

The light was changed from white to red on 1 July 1860.Throughout the 19th century, a series of improvements were made including converting the fuel source for the light to gas supplied from an on-site gas works. By far and away the most important of these alterations were carried out between 1891 and 1893, when the height of the tower was increased to 120 feet (37 m). The early 20th century saw further refinements to the lighthouse and 1902, when three black bands were added to the tower.

The gas burners were upgraded, and in 1908 an 920mm Chance Fresnel lens was installed.One of the county's best known landmarks, and rising over 40 meters above the rocky shore, St. John's point lighthouse is listed as one of twelve the "Great Lighthouses of Ireland" by the Commissioners of Irish Lights, who operate it as one of the 65 active lighthouses on the Irish coast.

Fully automated since 1981, the lighthouse has been painted black with two distinctive yellow bands since 1954, and operates a main light with a range of up to 29 miles (47 km), as well as auxiliary lights focused on warning passing craft of dangers in nearby Dundrum Bay. In addition to night-time operation, the light is in use during daylight hours when visibility is poor.

The daymark was changed to black with two yellow bands in 1954. The dwellings and the auxiliary light were provided with electricity. On 5 September 1957, the 084° bearing was altered to 078°. In this period, the lighthouse also established a curious connection with (then future) Irish playwright, Brendan Behan, who was employed as a painter at the lighthouse station. Seemingly unsuited to the task, the lightkeeper, one Mr. Blakely complained to the Commissioners of Irish Lights that Behan was "the worst specimen" he had met in 30 years' service and someone "not amenable to any law and order". Reportedly wasteful, poorly skilled, and indigent, Blakely requested Behan be dismissed "before the place is ruined", however, reportedly he was rehired for similar work the following year. The fog signal was discontinued on in January 2011 but the light is used during daylight hours when visibility is poor.

The former keepers' cottages and outbuildings have been operated by the Irish Landmark Trust and operated as tourist accommodation since 2015, however, access to the lighthouse tower is generally restricted and only open to public access on a limited basis.
Following on from a consultation process in 2015, the lighthouse was selected as one of the Irish Landmark Trust's capital projects, with restoration and increased access works to be undertaken in the period 2021/2022 and encompassing a range of improvements including:
* Retain the use of the existing rotating historic lens and sweeping beam
* Change the power system to mains with battery backup
* Remove mercury and diesel generator
* Replace filament lamps (1,000 watts) with LED (90 watts)
* Retain auxiliary light with LED equivalent
* Reduce the range of the light to 18 miles, as per 2010 and 2015 Aids to Navigation Reviews
* Remove interior wall lining and expose the original masonry of the lighthouse tower
* Provide opportunities for alternative use of buildings
* Reduce cost and maintenance requirements at the lighthouse
* Provide full range (18 mile) emergency lanterns