Hartham Weir
The 928th tallest dam in the world
Hartham Weir (also known colloquially as Two-step Weir) is a small weir on the River Lea next to the confluence of the River Beane/Lea, on the edge of Hartham Common, Hertford, England.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).