Ynys Gored Goch
The 928th tallest dam in the world
Ynys Gored Goch (Welsh for 'red weir island'), sometimes Ynys Gorad Goch, is a small island in the Menai Strait between Gwynedd and Anglesey in North Wales. It is situated in the stretch of the strait called the Swellies between Thomas Telford's Menai Suspension Bridge and Robert Stephenson's Britannia Bridge. The island is occupied by the main house and the converted smoke house where locally caught fish were processed. The island is private property and access is only by boat.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).