South Stack, Anglesey (Ynys Lawd, Ynys Môn)
| Location | SH 20242 82262 / 53.3067, -4.6993 / divide.live.florists |
| Established / Rebuilt / Automated / Closed | 1809 / — / 1984 / — |
| Architect or Builder | Daniel Alexander (built by Joseph Nelson) |
| Height of tower (m) / above sea level (m) / Range (NM) | 28 / 60 / 24 |
| Character | Fl 10s |
| Optic | 1st order rotating catadioptric |
| Owner | Trinity House |
Probably the most dramatically sited lighthouse in Wales, this tower on the rocky islet of Ynys Lawd is approached down 400 steps carved into a cliff face and over a bridge flung across a sea-raging chasm. The surrounding buildings have changed over the past two centuries, but the tower remains the same, other than a rebuilding of the lantern in 1874 when a Fresnel lens was installed. South Stack is operated by Trinity House and has tours every day from Easter to October, the only one in Wales open to the public.