Hook Head has the oldest nearly continuous light in Ireland, originally a signal fire or beacon tended by the monk Dubhán in the fifth century.

These acts, modified by the Irish Lights Commissioners (Adaptation) Order, 1935,[3] remain the legislative basis for the CIL.

[4] Irish Lights has moved its headquarters from Dublin to a purpose-built new building in Harbour Road, Dún Laoghaire.

The ship has diesel-electric propulsion and is extremely manoeuvrable, and is therefore ideal for her role in maintaining the automatic navigation buoys in Irish waters.

In 2003 she was involved in the recovery of the fishing boat Pisces, which sank off Fethard, County Wexford, in July 2002.

The current flag of the Irish Lights features lightships and lighthouses between the arms of the St. Patrick's Cross.