Tŵr Bach, Llanddwyn
| Location | SH 38674 62400 / 53.1343, -4.4130 / wires.lurching.decrease |
| Established / Rebuilt / Automated / Closed | Ca. 1800-1818 / — / 1975 / — |
| Architect or Builder | |
| Height of tower (m) / above sea level (m) / Range (NM) | 5 / 12 / 7 |
| Character | Fl WR 2.5s |
| Optic | LED |
| Owner | Natural Resources Wales |
One of two navigation towers on this picturesque tidal island, it was originally a simple unlit daymark guiding mariners into the southern entrance of the Menai Strait. It was later supplemented by the nearby Tŵr Mawr, a larger tower with a light. When that light was removed in 1975 an electric beacon was added to the top of this tower, which is still active.