Insane Megaprojects that were Never Builtbr #Buildingbr br #Megaprojectbr br #Constructionbr br From the Tallest Failed Skyscraper in America to the most Insane Airport Megaproject ever proposed, and from the World's Largest Dome to the Mile-High Illinois Skyscraper, here are the Most Insane Megaprojects that were Never Built! For more Megaproject & Skyscraper content be sure to subscribe to Our channel .