| Oystermouth Castle | |
|---|---|
| Oystermouth, Swansea, Wales | |
 Oystermouth Castle | |
| Type | Castle |
| Site information | |
| Owner | City and County of Swansea council |
| Open to the public | Yes |
| Condition | Ruin |
| Site history | |
| Built | 12th century |
| In use | 1106 to about 1650 |
| Materials | Stone |
Listed Building – Grade I | |
Oystermouth Castle (Welsh: Castell Ystum Llwynarth) is a Norman stone castle in Wales, overlooking Swansea Bay on the east side of the Gower Peninsula near the village of Mumbles.