Subiaco Dams
The 928th tallest dam in the world
The Subiaco Dams were a group of three Roman gravity dams at Subiaco, Lazio, Italy, devised as pleasure lakes for Emperor Nero (54–68 AD). The biggest one was the highest dam in the Roman Empire, and even in the world until its accidental destruction in 1305.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).