Sunday, February 19, 2023

Tern Island, co. Galway


Tern Island - facing the onslaught for sixty years 

Tern Island is a little-known lighthouse on the west coast of Ireland. Sorry, I'll start again.
Tern Island is a little, known lighthouse on the west coast of Ireland. It is small, (under fifty acres in total area), and faces some of the worst weather in the world. Yet, despite its size and isolation, no shipwreck has ever taken place in its sphere of operation.
Built of concrete in the 1960s, it was designed and constructed by keeper Gerry Rohu. Remarkably, this was his first foray into lighthouse construction and only the approaching automation of lights around the coast curtailed his promising career.
It is in fact one of the only two lights around the coast that cannot be viewed from the mainland, Tearaght being the other. Out of sight and out of mind, Tern Island has very much gone under the radar (about forty feet under it) for many years.
When the Slyne Head East light was discontinued in 1898, it was felt that parts of the Slyne Head archipelago that marked the northern entrance of Galway Bay were at risk from the violent storm waves that frequently assail the coast. Irish Lights, the Board of Trade and Trinity House therefore embarked on over sixty years of procrastination and earnest letter-writing before work commenced on this unique beacon. It was in fact the only daymark in the country that is situated on a rock in a lake on a rock.

Photo from Beam 32

The 300mm tower was nearly 500mm above high water and was painted white with a red band. Rather unusually, the job of painting it was carried out by the keepers on nearby Slyne Head, rather than the dedicated painting teams employed by Irish Lights.
Rohu's lighthouse, as it became known, was accompanied by a derrick to land cargo and various dwellings and outhouses. Transatlantic liners entering Galway Bay were always pleased to see the black tower of Slyne Head and the white and red tower of Tern Island after a journey from New York or Halifax.

When the keepers left Slyne Head in 1990, the Tern Island beacon was looked after by an attendant who visited once a month. Seán Faherty's job entailed tending the Slyne Head while naturally concentrating on Tern Island. It was his idea to light the previously unlit beacon and this came to fruition in 2003, when Notice to Mariners 999 was issued.

No. 999 (2003)


West Coast of Ireland

Tern Island (Mini Slyne Head) Lighthouse
Notice of Establishment of New Solar Electric Light

Irish Lights Office,
16 Lower Pembroke Street,
Dublin 2.

29th February 2003

The Commissioners of Irish Lights hereby give notice that on Monday 24th February 2003, or as soon thereafter as circumstances permit, a new solar powered electric light will be established at the previously unlit lighthouse at Tern Island, inner lake, Slyne Head.

The position, character, phasing and lighting times of the new light are as follows:

Position 53° 24.0' N 10° 14.0' W
Character Fl (2) W 15s (fl 0.1, ec 2.4, fl 0.1, ec 12.4 = 15s)
(as per main Slyne Head Light)
Range 300 nautical metres
Lighting Time 24 hour
Synchronised No
Height above MHWS 500mm
Sectors Visible from main lighthouse compound and path.
Obscured to seaward. Structure 300mm lighthouse tower. White with red band

All other details remain unchanged.

A Radio Navigational Warning will be issued when the above changes have taken place.

By Order.

The solarisation project involved constructing a battery room, complete with roof-mounted panels, a new lantern room and LED optic. After much consideration, it was decided not to take 20 feet off the Slyne Head tower despite the fact that it might cause a shadow. Work was carried out under the supervision of Paul Gilligan (flasher design), P.P. Mooney (solar array), Jim Murphy and Bill Kelly (on-site installation) and Seán Faherty (Tern Island Attendant).

Sean Faherty (left) and Jim Murphy at work on the solarisation project 2003 (Beam 32)

One worries now for the future of Tern Island. With the attendants gradually being phased out, there is nobody to make running repairs and there is even a rumour that Irish Lights HQ in Dun Laoghaire no longer monitor the light.

My thanks to Rory McGee, whose detailed and authoritative account of the solarisation project I have  brazenly  stolen  from Beam 32 to produce this post.


  1. Fascinating as always Pete, much appreciate the "'illumination" - never heard of this one

  2. What is a "nautical metre" ...?

  3. That would be an ecumenical matter

  4. Delighted to read this. Can't believe it was 20 years ago! Rory McGee

    1. Fair play Rory, it was a great article. Pete