Two attempts were made in 1849 and 1857 to establish a lighthouse on Galley Head, each time with the Board's approval but both were turned down by Trinity House; they did say however that they would sanction a local light which would not be a burden on general trading vessels.
Fourteen years elapsed before Galley Head was mentioned again, this time by Lord Bandon in a letter to the Board calling their attention to the number of wrecks off the headland. Also a number of other letters were received about the same time on the same subject. The Board checked the number of wrecks with Admiral Forbes, Commander-in-Chief, British Navy at Queenstown, Cork Harbour and the subject was referred to the Inspecting Committee who reported in March 1871. A copy of the report together with correspondence was forwarded to the Board of Trade in London who in turn passed the information on to Trinity House. Sanction from both bodies in London was received during the following month, April.
Towards the end of May, Lord Bandon and the inhabitants of Rosscarbery expressed their thanks to the Elder Brethren and the Board for sanctioning a lighthouse on Galley Head.
Land for the lighthouse, together with an access right of way, was negotiated over a period of two years and the lease was sealed in 1873.
The contract for the buildings including the tower, except the lantern, went to William M. Murphy of Bantry and was carried out between 1873 and 1875.
Around this period great interest was shown in using gas made from cannel coal as the source of illumination for optics.
Messrs J. Edmundson & Co. of Dublin with their engineer John R. Wigham were fore-runners in promoting this form of lighting and therefore, not surprisingly, they supplied the gas making plant, lantern and French manufactured first order dioptric quadriform optic.
The station was designed by Mr J. S. Sloane, Engineer-in-Chief and consisted of a tower connected by a 38m (125 foot) long corridor to the semi-detached, two storey, dwelling for the principal and assistant keeper, a single storey dwelling for the gas maker and the gas works located behind the dwellings.
The light was established on 1 January, 1878 with a character of six or seven white flashes in sixteen seconds followed by a forty-four second period of darkness. This somewhat unusual character was due to the combination of an eight-sided optic revolving once every minute and the multiple jet gas burners being turned on and off approximately once every two seconds. Consequently it was possible for vessels in certain positions to miss one of the flashes. The tower 21m (69 feet) high was and still is painted white including the lantern and dome. The focal plane of the light is 53m (174 feet) above high water and the original light could be seen in clear weather for 30km (19 miles). At the time this was the most powerful lighthouse light in the world.
Normally only one tier of the four superimposed optics was used but as the weather deteriorated another tier was lit until all four tiers were in use for fog conditions. Each optic burner had seven concentric rings of fish-tail jets, 108 jets in all, 432 if the complete quadriform optic was in use.
If the gas supply failed then a multi concentric wick oil lamp was fitted to the lower tier as a standby.
Six and a half faces of the lantern have clear glazing covering a seaward bearing 256° through west to 065° and nine and a half faces are blanked off towards the land except for six panes in two faces which have been left clear. The reason, so the story goes, for these clear panes in the dark landward arc goes back to the time when the Sultan of Turkey was staying with Lord Carbery at Castle Freke. He wanted to know what the tower was on the distant headland and was told that it was a lighthouse which shone out at night over the sea. Still not satisfied he then wanted to know why should it not shine over the land. Lord Carbery must have had friends in the right places because the end result was that four panes on two sides were fitted with clear glass. I still have to confirm this story in the Board's minutes but the story does not end there. After the light was converted to electric in 1969 Mr A.D.H. Martin the Engineer-in-Chief agreed that the panes should be painted out so that the much brighter light would not be a dazzling hazard to local motorists. Two months later Dr M.D. Hegarty of Ross Carbery backed up by a number of local people asked if they could have the light flashing towards land again, at diminished strength. This was agreed and two of the top tier landward panes were made clear.
After the Inspecting Committee's Tour in 1904 they recommended that the light and optic should be converted from quadriform gas to biform incandescent paraffin, giving a group of five flashes every twenty seconds. Trinity House and the Board of Trade gave their sanction the following year and the new first order optic and pedestal, manufactured by Chance Brothers, were installed in 1907. The light was exhibited on 18 June, 1907, its candle power increased to 362,000 and range to 38km (24miles).
The 1963 Inspecting Committee recommended converting the light to electric and making the station unwatched manned by a Principal Keeper; the conversion was included in the 1967/68 Estimates.
The existing biform optic was retained using the upper optic for the main light fitted with a lamp changer and two 3.5kw electric filament lamps, one in use the other as a standby. A standby mains failure diesel generating set was located in the bottom of the tower. Conversion to electric was completed on 20 August 1969; the candlepower was increased from 362,000 to 2,800,000 with a range of 23 nautical miles. The Assistant Keeper was withdrawn and the Principal Keepers' wife was appointed Female Assistant Keeper.
Galley Head Lighthouse was converted to automatic operation in 1978-9. This entailed installing a gearless drive to rotate the optic and a monitoring system in the dwelling to alert the Attendant in the event of a fault. The Principal Keeper retired on 28 February 1979 and was appointed Attendant from the following day.
The main optic lamps were changed from 3.5 kW filament lamps to 1kw metal-arc lamps from 27 November 1990.
Emergency lanterns, designed to switch on automatically should the main light fail, were installed in 1991.
The requirement for the Attendant to live at the station was discontinued from 1 July 1997 and modifications were made to the station to allow this. The tower corridor was sealed off from the dwellings. Control cabinets and batteries were relocated, electrical supplies and domestic services were re-arranged, and security and fire protection systems were provided. A remote control and monitoring system linking the station to the central monitoring room at Dun Laoghaire was installed.
Discussions with Irish Landmark Trust commenced in 1998 the eventual outcome of which was an arrangement whereby the two Keepers' dwellings were leased to the Trust, which restored them to their original symmetrical layout using traditional materials and building methods. Restoration of the dwellings was completed in March 2002. The restored dwellings are now let to the general public by Irish Landmark Trust as holiday accommodation.