alternatehistory.com

Here you can list megastructure projects which abandoned due to lack of willingness, technology, funding, etc, in OTL but have a chance of being built in other timelines. Or they can still be ideas in our world.

First in my mind are the Atlantropa, the "greening" of Sahara desert, and the redirection of Central Asian rivers for irigation.
Can you name more? I really need this.

Thanks in advance!
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