The lighthouse stands 19.2m (63ft) high with a roll-moulded string-course projecting above first floor level, and is unusual in being (6.78m - 22ft 3in) square in plan. A moulded cornice supports a walkway around the circular lantern and the domed apex is surmounted by a weathervane and finial. This three-storeyed lighthouse is painted black and white with chamfered angles and a stepped plinth set on an oval platform on the breakwater.

Event and Historical Information:
This lighthouse is important for being part of the ambitious engineering works of the harbour of refuge. It was erected at the end of the long breakwater (nprn 41258) protecting the harbour of refuge. The lighthouse was built between 1845 and 1873 and probably designed by John Hawkshaw, the superintendent engineer of the harbour works from 1857 to 1873. Like most other lights in Gwynedd, this is now operated from the Holyhead Control Centre of Trinity House.

Sources include:
Cadw Listing Documentation
Hague, D, 1994, Lighthouses of Wales: Their Architecture and Archaeology, pg55

Maritime Officer, December 2008.