Holyhead Admiralty Pier, Salt Island (Caergybi, Ynys Halen)
The current lighthouse at the tip of Admiralty Pier replaced an earlier one that stood on Salt Island and was erected as part of a major development of Holyhead Harbour. It has a twin in the port of Howth at the other end of the Wales-Ireland packet ship route. The light fell into disuse in the 1870s when the inner harbour was redeveloped, although for many years it supported a pair of red and green lights on a pole that indicated if the inner harbour was open.
| Location | SH 25564 82904 / 53.3143, -4.6199 / status.tennis.dolly |
| Established / Rebuilt / Automated / Closed | 1821 / — / — / 1870s |
| Architect or Builder | John Rennie |
| Height of tower (m) / above sea level (m) | 15 / — |
| Owner | Stena Line |