Great South Wall
The 928th tallest dam in the world
The Great South Wall (Irish: Balla an Bhulla Theas) (also sometimes called the South Bull Wall) is a sea wall at the Port of Dublin, Ireland. It extends from the tip of the Poolbeg peninsula more than four kilometres out into Dublin Bay. It was the world's longest sea wall at the time of its construction in the 18th century and remains one of the longest in Europe. It faces the newer Bull Wall, and has one of four port lighthouses at its end.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).