Red Sea Dam
The 928th tallest dam in the world
The Red Sea Dam is a speculative macro-engineering proposal put forward in 2007 by a group of scientists and engineers. Although the authors' intentions are to explore "the ethical and environmental dilemmas and some of the political implications of macro-engineering", the proposal has attracted both criticism and ridicule.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).